


I LIBRARY OF CONGRESS. I 

Jio . '.v| 

Cljap.^'7 
No. .^3 

^|l DNITED STATES OF aIeMCA. I, 

■; .•- .;. .V .;. .|. .•. ■•;». v. ... ... K'^J^'sr? * 



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REVISED EDITION. 



ACCOMPANIED BY 



A CELESTIAL ATLAS 



BY ELIJAH H. BURRITT, A. M. 



A NEW EDITION, 

REVISED AND ILLUSTRATED. 

BY HIRAM MATTISON, 

■■■ ■!- 

PROFESSOR OF NATURAL PHILOSOPHY AND ASTRONOMY IN THE PALLET 

SEMINARY ; A IT HO R OF THE PRIMARY ASTRONOMY, ELEMENTARY 

ASTRONOMY, ASTRONOMICAL MAPS, ETC.. ETC 



NEW YORK: 

F. J. HUNTINGTON, 

AND 

MASON & LAW, 23 PAKE ROW, 

OPPOSITE THE ASTOR HOUSE. 



THE 



GEOGRAPHY OF THE HEAVENS, 



CLASS-BOOK OF ASTRONOMY: 






1853. 



SB}? 



V* 



Entered according to Act of Congress., in the year 1349, 

By HUNTINGTON AND SAVAGE. 

in the Clerk's Office of the District Court for the Soathem District 

of New York. 



Stereotyped by C. Davison.. 
33 Gold st, N. Y. 



PUBLISHERS' NOTICE. 



In presenting a new edition of this work to the public, it is 
proper to point out several very important improvements which 
have been made. 

The work has been thoroughly revised, from beginning to end, 
by one of the most competent Astronomers in the country. In 
this revision all errors and discrepancies between the book and 
the Atlas have been corrected, and the work brought down to the 
present improved state of the science, by the incorporation of all 
recent discoveries. 

The Atlas also has been improved by the addition of several 
new figures, and the correction of numerous errors ; so that the 
work as a whole may not only be regarded as eminently full and 
complete, but as in the highest degree accurate. 

In the second part of the work great improvements have been 
made in the number and quality of- the illustrations. Not only 
have most of the old ones been re-engraved and improved, but the 
work has been enriched by the addition of about fifty new cuts. 
This of itself will materially enhance the value of the book. 

In the prosecution of his labors the Editor has availed himself 
of the correspondence of several eminent Teachers and Scholars, 
among whom are Dr. Dick, of Scotland, Mr. L. A. Miller of 
Woodstock, Vt.; and W. H. Wells, M. A., of Newburyport, Mass. 
The communications of these gentlemen, especially, have done 
much to facilitate the work of revision, and have contributed not a 
little to the present accuracy and completeness of the book. 

That the letter-press of the book might correspond with the im- 
provements in the text, and the new and beautiful illustrations, * 
the whole has been re-stereotyped and now appears in a dress 
worthy of its character, as a well-known, popular and standard 
work. We commend it to teachers as more than ever entitled to 
their confidence and patronage. 



PREFACE. 



I have long felt the want of a Class Book, which should be to the 
starry heavens, what Geography is to the earth ; a work that should 
exhibit, by means of appropriate delineations, the scenery of the 
heavens : the various constellations arranged in their order, point 
out and classify the principal stars, according to their magnitudes 
and places, and be accompanied, at the same time, with such 
familiar exercises and illustrations, adapted to recitation, as should 
bring it within the pale of popular instruction, and the scope of 
juvenile understandings. 

Such a work I have attempted to supply. I have endeavored to 
make the descriptions of the stars so familiar, and the instructions 
for finding them so plain, that the most inexperienced should not 
fail to understand them. In accomplishing this, I have relied but 
little upon globes and maps, or books. I very early discovered 
that it was an easy matter to sit down by a celestial globe, and, by 
means of an approved catalogue, and the help of a little graduated 
slip of brass, make out, in detail, a minute description of the 
stars, and discourse quite familiarly of their position, magnitude 
and arrangement, and that when all this was done, I had indeed 
given the pupil a few additional facilities for finding those stars 
upon the artificial globe, but which left him, after all, about as 
ignorant of their apparent situation in the heavens, as before. I 
came, at length, to the conclusion, that any description of the stars, 
to be practically useful, must be made from a careful observation 
of the stars themselves, and made at the time of observation. 

To be convinced of this, let any person sit down to a celestial 
globe or map, and from this alone, make out a set of instructions 
in regard to some favorite constellation, and then desire his pupil 
to trace out in the firmament, by means of it, the various stars 
which he has thus described. The pupil will find it little better 
than a fancy sketch. The bearings and distances, and especially, 
the comparative brightness, and relative positions, will rarely be 
exhibited with such accuracy that the young observer will be in- 
spired with much confidence in his guide. 

I have demonstrated to myself at least, that the most judicious 
instructions to put on paper for the gu ide of the young in this study 
are those which I have used most successfully, while in a clear 
evening, without any chart but the firmament above, I have 
pointed out, with my finger, to a group of listeners, the various 
stars which compose this and that constellation. 

In this way, the teacher will describe the stars as they actually 
appear to the pupil — taking advantage of those obvious and more 
striking features that serve to identify and to distinguish them 
from all others. Now if these verbal instructions be committed to 



writing and placed in the hands of any other pupil, they will an- 
swer nearly the same end. This is the method which I have pur- 
sued in this work. The descriptive part of it, at least, was not 
composed by the light of the sun, principally, nor of a lamp, but 
by the light of the stars themselves. Having fixed upon the most 
conspicuous star, or group of stars, in each constellation, as it 
passed the meridian, and with a pencil carefully noted all the 
identifying circumstances of position, bearing, brightness, number 
and distance — their geometrical allocation, if any, and such other 
descriptive features as seemed most worthy of notice, I then re- 
turned to my room to transcribe and classify these memoranda in 
their proper order ; repeating the same observations at different 
hours the same evening, and on other evenings at various periods, 
for a, succession of years; always adding such emendations as sub- 
sequent observations matured. To satisfy myself of the applica- 
bility of these descriptions, I have given detached portions of them 
to different pupils, and sent them out to find the stars ; andl" have 
generally had the gratification of hearing them report, that "every 
thing was just as I had described it." If a pupil found any diffi- 
culty in recognizing a star, I re-examined the description to see if 
it could be made better, and when I found it susceptible of im- 
provement, it was made on the spot. It is not pretended, however, 
that there is not yet much room for improvement ; for whoever 
undertakes to delineate or describe every visible star in the heav- 
ens, assumes a task, in the accomplishment of which he may well 
claim some indulgence. 

The maps which accompany the work, in the outlines and ar- 
rangement of the constellations, are essentially the same with 
those of Dr. Wollaston. They are projected upon the same prin- 
ciples as maps of Geegraphy, exhibiting a faithful portraiture of 
the heavens for every month, and consequently for every day in the 
year, and do not require to be rectified, for that purpose, like globes. 

They are calculated, in a good measure, to supersede the neces- 
sity of celestial globes in schools, inasmuch as they present a more 
natural view of the heavenly bodies, and as nearly all the prob- 
lems which are peculiar to the celestial globe, and a great num- 
ber besides, may be solved upon them in a very simple and satis- 
factory manner". They may be put into the hands of each indi- 
vidual in a class at the same time, but a globe cannot be. The 
student may conveniently hold them before his eye to guide 
his survey of the heavens, but a globe he cannot. There is not a 
conspicuous star in the firmament which a child of ten years may 
not readily find by their aid. Besides, the maps are always right 
and ready for use, while the globe is to be rectified and turned to 
a particular meridian ; and then if it be not held in that position 
for the time being it is liable to be moved by the merest accident 
or breath of wind. 

There is another consideration which renders an artificial globe 
of very little avail as an auxiliary lor acquiring a knowledge of 
the stars while at school. It is this; — the pupil spends one, per- 
haps two weeks, in solving the problems, and admiring the fig- 
ures on it, in which time it has been turned round and round a 
1* 



hundred times; it is then returned safely to its case, and some 
months afterwards, or it may be the next evening, he directs his 
eye upwards to recognize his acquaintance among the stars. He 
may find himself able to recollect the names of the principal stars, 
and the uncouth forms by which the constellations are pictured 
out ; but which of all the positions he has placed the globe in, is 
now so present to his mind that he is enabled to identify it with 
any portion of the visible heavens 1 
He looks in vain to see 

" Lions and Centaurs, Gorgons, Hydras rise. 
And gods and heroes blaze along the skies." 

He finds, in short, that the bare study of the globe is one thing, 
and that of the heavens quite another; and he arrives at the con- 
clusion, that if he would be profited, both must be studied and 
compared together. This, since a class is usually furnished with 
but one globe, is impracticable. In this point of view also, the 
maps are preferable. 

I have endeavored to teach the Geography of the heavens in 
nearly the same manner as we teach the Geography of the earth. 
What that does in regard to the history, situation, extent, popula- 
tion and principal cities of the several kingdoms of the earth, 1 
have done in regard to the constellations ; and 1 am persuaded, 
that a knowledge of the one may be as easily obtained, as of the 
other. The systems are similar. It is only necessary to change 
the terms in one, to render them applicable to the other. For this 
reason, I have yielded .to the preference of the publisher in calling 
this work " Geography of the Heavens," instead of Uranograpiiy, 
or some other name more etymologically apposite. 

That a serious contemplation of those stupendous works of. the 
Most High, which astronomy unfolds, is calculated above all 
other departments of human knowledge, to enlarge and invigorate 
the powers of religious contemplation, and subserve the interests 
of rational piety, we have the testimony of the most illustrious 
characters that have adorned our race. 

If the work which I now submit, shall have this tendency, I shall 
not have written in vain. Hitherto, the science of the stars has 
been but very superficially studied in our schools, for want of 
proper helps. They have continued to gaze upon the visible 
heavens without comprehending what they saw. They have cast 
a vacant eye upon the splendid pages of this vast volume, as chil- 
dren amuse themselves with a book which they are unable to read. 
They have caught here and there, as it were, a capital letter, or a 
picture, but they have failed to distinguish those smaller charac- 
ters on which the sense of the whole depends. Hence, says an 
English Astronomer, "A comprehensive work on Descriptive As- 
tronomy, detailing, in a popular manner, all the facts which have 
been ascertained respecting the scenery of the heavens, accom- 
panied with a variety of striking delineations, accommodated to the 
capacity of youth, is a desideratum. 7 ' How far this desirable end 
is accomplished by the following work, I humbly leave to the 
public to decide. 

Hartford, Feb. 1833. 



INDEX. 



PAGE 

Andromeda, 35 

Aries, the Ram. 43 

Auriga, the Charioteer, 63 

Argo Xavis, the Ship Argo, 74 

Asterion et Chara, vel Canes Venatici, 

the Greyhounds. 94 

Aquila et Antinous, the Eagle and An- 
tinous, 125 

Aquarius, the Water-Bearer, 135 

Asteroids, 233 

Aurora Borealis, the Northern Lights,- 309 

Bootes, th^e Bear-Driver, 95 

Cassiopeia, 33 

Cepheus. 41 

"^etus, the Whale, 47 

Columba the Dove, 61 

Camelopardalus, the Camelopard. — 65 

Canis Minor, the Little Dog, 69 

Canis Major, the Great Dog, 71 

Cancer, the Crab, 76 

Coma Berenices, Berenice's Hair,-"- 89 

Corvus, the Crow, 90 

Centaurus, the Centaur, 93 

Corona Borealis, the Northern Crown,. 103 

Cygnus, the Swan, 123 

Capricornus, the Goat, 131 

Constellations — origin of, 146 

Comets, 252 

Draco, the Dragon, 117 

Delphinus, the Dolphin, 127 

Dick's Introduction, viii 

Geography, viii 

Navigation, ix 

Agriculture, x 

Chronology, xi 

Propagation of Religion. xii 

Dissipates Superstitious Notions,-, xiii 
Days and Nights, different lengths of,- • 297 

Eridanus, River Po, 61 

Equulus, vel Equi Sectio, the Little 

Horse, or the Horse's Head, 134 

Earth, 199 

Equinoxes— Precession of, 275 

Ecliptic— Obliquity of, 282 

Eclipses, Solar and Lunar, •• 219 

Forces, Attractive and Projectile, 271 

Gemini, the Twins, 63 

Gravitation, Universal Law of, 267 

Hydra, the Water Serpent, and the 

Cup. 

Hercules, .._ 

Herschel. 243 

Heavenly Bodies— Parallax of, 312 



PAGB 

Jupiter, 237 

Lepus, the Hare, — 60 

Lynx, 65 

Leo, the Lion, 78 

Leo Minor, the Little Lion, 82 

Lupus, the Wolf, 99 

Libra the Balance, 100 

Lyra, the Harp. 121 

Monoceros, the Unicorn, 71 

Mars, 229 

Mercury, 183 

Moon, 210 

Moon— Harvest and Horizontal, 299 

Meteoric Showers, Professor Olmsted's 

Remarks upon. 167 

Neptune, 249 

Orion, 56 

Pisces, the Fishes, 36 

Perseus et Caput Medusae, Perseus and 

Medusa's head, 49 

Pegasus, the Flying Horse, 133 

Piscis Australis, vel Notius, the South- 
ern Fish, 136 

Preliminary Chapter, 25 

Planets, forces by which they are re- 
tained in their Orbits, 267 

Problems and Tables, 314 

Refraction. 302 

Sextans, the Sextant, 82 

Serpens, the Serpent, 102 

Scorpio, the Scorpion, 109 

Sagittarius, the Archer, 124 

Serpentarius, vel Ophiuchus, the Ser- 
pent-Bearer. 115 

Stars— variable, ■ 137 

Double, 133 

Clusters of,.---." 141 

Nebulae. 142 

Number, Distance, and Economy 

of. 152 

Falling, or Shooting. 168 

Solar System— General Phenomena of, 169 

Sun, 173 

Sun, proper motion of the, in space,- 273 

Saturn, 242 

Seasons, 293 

Taurus, the Bull, 52 

Tides, 284 

Ursa Major, the Great Bear, BE 

Wsa Minor, the Little Bear, 105 

Virgo, the Virgin. 92 

Via Lactea, the Milky Way, 144 

Venus, 13S 



INTRODUCTION, 



ADVANTAGES OF THE STUDY OF ASTRONOMY. 

BY 
THOMAS DICK, LL. D. 



Astronomy is a science which has, in all ages, engaged the at- 
tention of the poet, the philosopher, and the divine, and been the 
subject of their study and admiration. Kings have descended from 
their thrones to render it homage, and have sometimes enriched it 
with their labors ; and humble shepherds, while watching their 
flocks by night, have beheld with rapture the blue vault of heaven, 
with its thousand shining orbs moving in silent grandeur, till the 
morning star arinounced the approach of day. The study of this 
science must have been co-eval with the existence of man. For 
there is no rational being who, for the first time, has lifted his eyes 
to the nocturnal sky, and beheld the moon walking in brightness 
among the planetary orbs and the host of stars, but must have been 
struck with awe and admiration at the splendid scene, and its sub- 
lime movements, and excited to anxious inquiries into the nature, 
the motions, and the destinations of those far-distant orbs. Com- 
pared with the splendor, the amplitude, the august motions, and 
the ideas of infinity which the celestial vault presents, the most 
resplendent terrestrial scenes sink into inanity, aad appear un- 
worthy of being set in competition with the glories of the sky. 

Independently of the sublimity of its objects, and the pleasure 
arising from their contemplation, Astronomy is a study of vast 
utility, in consequence of its connection with terrestrial arts and 
sciences, many of which are indebted to the observations, and the 
principles of this science, for that degree of perfection to which 
they have attained. 

Astronomy has been of immense utility to the science of 

GEOGRAPHY; - 

for it is chiefly in consequence of celestial observations that the 
true figure of the earth has been demonstrated and its density as- 
certained. It was from such observations, made on the mountain 
Schehallien in Scotland, that the attraction of mountains was de- 
termined. The observations were made by taking the meridian 
distances of different fixed stars near the zenith, first on the south, 
and afterwards on the north side of the hill, when the plumb line 
of the Sector was found, in both cases, to be deflected from the 



INTRODUCTION. IX 

perpendicular towards the mountain; and, from calculations 
founded on the quantity of this deflection, the mean density of the 
earth was ascertained. It was likewise by means of celestial ob- 
servations that the length of a degree of the meridian was measur- 
ed, and the circumference of the globe, with all its other dimen- 
sions, accurately ascertained; for, to ascertain the number of 
degrees between any two parallels on the Earth's surface, observa- 
tions must be taken, with proper instruments, of the sun or of the 
stars, at different stations; and the accurate measurement of the 
terrestrial distance between any two stations or parallels, partly 
depends on astronomical observations combined with the princi- 
ples and operations of Trigonometry. So that without the aids of 
this science, the figure and density, the circumference and diame- 
ter of our terrestrial habitation, and the relative position of places 
on its surface, could never have been ascertained. 
Astronomy is likewise of great utility to the art of 

NAVIGATION; 

without a certain knowledge of which the mariner could never 
have traced his course through pathless oceans to remote regions 
— the globe would never have been circumnavigated, nor an inter- 
course opened between the inhabitants of distant lands. It is of 
essential importance to the navigator, not only to know the situa- 
tion of the port to which he is bound, but also to ascertain with 
precision, on what particular portion of the terraqueous globe he 
is at any time placed — what course he is pursuing — how far he 
has traveled from the port at which he embarked — what danger- 
ous rocks or shoals lie near the line of his course — and in what 
direction he must steer, in order to arrive, by the speediest and the 
safest course, to his destined haven. It is only, or chiefly, by as- 
tronomical observations that such particulars can be determined. 
By accurately observing the distance between the moon and cer- 
tain stars, at a particular time, he can calculate his distance East 
or West from a given meridian; and, by taking the meridian 
altitude of the sun or of a star, he can learn his distance from the 
Equator or from the poles of the world. In such observations, a 
knowledge of the constellations, of the pole-star, and of the general 
positions of all the stars of the first and second magnitude, is of 
particular importance ; and, therefore, a navigator who is unac- 
quainted with the science of the heavens, ought never to be ap- 
pointed to conduct a ship through the Indian, the Atlantic, or the 
Pacific oceans, or through any portions of the sea which are not 
within sight of land. By the observations founded on astronomi- 
cal science, which have been made in different regions by mari- 
ners and travelers ot various descriptions, the latitudes and 
longitudes of the principal places on the globe, and their various 
bearings and relations have been determined, so that we can now 
take a viewof the world we inhabit in all its multifarious aspects, 
and direct our course to any quarter of it, either for business, fur 
pleasure, or for the promotion of philanthropic objects. Thus, 
Astronomy has likewise become of immense utility to Trade and 
Commerce, in opening up new emporiums for our manufacture, in 



X INTRODUCTION. 

augmenting and multiplying the sources of wealth, in promoting 
an intercourse between the most distant nations, and enabling us 
to procure, for our accommodation or luxury, the productions of 
every climate. If Science has now explored almost every region ; 
if Politics and Philosophy have opened a communication between 
the remotest inhabitants of the globe; if alliances have been form- 
ed between the most distant tribes of mankind; if Traffic has 
explored the multifarious productions of the earth and seas, and 
transported them from one country to another, and, if heathen 
lands and barbarous tribes have been " visited with the Day-spring 
from on high, and the knowledge of salvation." — it is owing to 
the aids derived from the science of the stars, without which the 
continents, the islands, and the different aspects of our globe 
would never have been explored by those who were separated 
from them by intervening oceans. 

This science has been no less useful to 

AGRICULTURE 

and to the cultivators of the earth. The successful cultivation ol 
the soil depends on a knowledge of the course of the sun, the exact 
length of the seasons, and the periods of the year most proper for 
the operations of tillage and sowing. The ancients were directed 
in these operations, in the first instance, by observing the courses 
of the moon, and that twelve revolutions of this luminary cor- 
responded nearly with one apparent revolution of the sun. But 
finding the coincidence not exact, and that the time of the seasons 
was changing — in order to know the precise bounds of the sun's 
annual course, and the number of days corresponding to his ap- 
parent yearly revolution, they were obliged to examine with care 
what stars were successively obscured in the evening by the sun, 
or overpowered by the splendor of his light, and what stars were 
beginning to emerge from his rays, and to re-appear before the 
dawn of the morning. By certain ingenious methods, and nu- 
merous and attentive observations, they traced out the principal 
stars that lay in the line of the sun's apparent course, gave them 
certain names by which they might be afterwards distinguished, 
and then divided the circle of the heavens in which the sun ap- 
pears to move, first into quadrants, and afterwards into 12 equal 
parts, now called the signs of the Zodiac, which they distinguished 
by names corresponding to certain objects and operations con- 
nected with the different seasons of the year. Such were the 
means requisite to be used for ascertaining the length of the year, 
and 'he commencement of the different seasons, and for directing 
the labors of the husbandman ; and, were the knowledge of these 
things to be obliterated by any extensive moral or physical con- 
vulsion, mankind would again be under the necessity of having 
recourse to astronomical observations for determining the limits 
of the solar year, and the course of the seasons. Although we 
find no difficulty, in the present day, and require no anxious ob- 
servations, in determining the seasons, yet, before astronomical 
observations were made with some degree of accuracy, the ancient 
Greeks had to watch the rising of Arc/urn*, the Pleiades and Orion, 



INTRODUCTION. XI 

to mark their seasons, and to determine the proper time for their 
agricultural labors. The rising of the star Sirius along with the 
sun, announced to the Egyptians the period when they might ex- 
pect the overflowing of the Nile, and, consequently, the time when 
they were to sow their grain, cut their canals and reservoirs, and 
prepare the way for their expected harvest. 

The science of 

CHRONOLO GY 
likewise depends on celestial observations. The knowledge of an 
exact measure of time is of considerable importance in arranging 
and conducting the affairs of life, without which, society in its 
movements would soon run into confusion. For example, if we 
could not ascertain, within an hour or two, when an assembly 
or any concourse of human beings was to meet for an important 
purpose, all such purposes would soon be frustrated, and human 
improvement prevented. Our ideas of time or succession in dura- 
tion, are derived from motion ; and in order to its being divided 
into equal parts, the motions on which we fix as standards of 
time must be constant and uniform, or at least, that any slight 
deviation from uniformity shall be capable of being ascertained. 
But we have no uniform motion on earth by which the lapse of 
duration can be accurately measured. Neither the flight of birds, 
the motion of the clouds, the gentle breeze, the impetuous whirl- 
wind, the smooth-flowing river, the roaring cataract, the falling 
rain, nor even the flux and reflux of the ocean, regular as they 
generally are, could afford any certain standard for the measure 
of time. It is, therefore, to the motion of the celestial orbs alone 
that we can look for a standard of duration that is certain and in- 
variable, and not liable to the changes that take place in all terres- 
trial movements. Those magnificent globes which roll around us 
m the canopy of the sky — whether their motions be considered as 
real or only apparent, move with an order and regularity which is 
not found in any physical agents connected with our globe ; and 
when from this quarter we have derived any one invariable mea- 
sure of time, we can subdivide it into the minutest portions, to 
subserve all the purposes of civil, life, and the improvements of 
science. Without the aids of astronomy, therefore, we should have 
had no accurate ideas of the lapse of time, and should have been 
obliged, like the rude savage of the desert, to compute our time by 
the falls of snow, the succession of rainy seasons, the melting of 
the ice, or the progress and decay of vegetation. 

Celestial observations, in consequence of having ascertained a 
regular measure of time, have enabled us to fix chronological dates, 
and to determine the principal epochs of History. Many of those 
epochs were coincident with remarkable eclipses of the sun or 
moon, which the ancients regarded as prognostics of the loss of 
battles, the death of monarchs, and the fall of empires ; and which 
are recorded in connection with such events, where no dates are 
mentioned. The astronomer, therefore, knowing the invariable 
movements of the heavenly orbs, and calculating backwards 
through the past periods of time, can ascertain what remarkable 
eclipses must have been visible at any particular time and place 



Xll INTRODUCTION. 

and consequently, can determine the precise date of contemporary 
events. Calvisius. for example, founds his Chronology on 14-1 
eclipse.'- of the sun, and 127 of the moon, which he had calculated 
for the purpose of determining epoc.has and settling dates. The 
grand conjunction of the planets Jupiter and Saturn, which occurs 
once in 800 years, in the same point of the zodiac, and which has 
happened only eight times since the Mosaic Creation, furnishes 
Chronology with incontestable, proofs of the date of events, when 
such phenomena happen to be recorded. On such data, Sir Isaac 
Newton determined the period when Thales the philosopher flour- 
ished, particularly from the famous eclipse which he predicted, 
and which happened just as the two armies under AlyaUes, king 
of Lydia, and Cyaxares the Mede were engaged; and which has 
been calculated to have happened in the 4th year of the 431 Olym- 
piad, or in the year before Christ G03. On similar grounds Dr. 
Halley, a celebrated astronomer of the last century, determined 
the very day and hour of the landing of Julius Cesar in Britain, 
merely from the circumstances stated in the : ' Commentaries " of 
that illustrious general. 

Astronomy has likewise lent its aid lo the 

PROPAGATION OF RELIGION, 

and the conversion of the heathen world. For without the light 
derived from this celestial science, oceans would never have been 
traversed, nor the continents and islands explored where benighted 
nations reside, and, consequently, no messengers of Peace could 
have been dispatched to teach them " the knowledge of salvation, 
and to g'.iide their steps in the way of peace." But, with the di- 
rection afforded by the heavenly orbs c.nd the magnetic needle, 
thousands of Christian missionaries, £ long with millions of bibles, 
may now be transported to the most distant continents and islands 
of the ocean, to establish among them th • ; Law and Testimony " 
of the Most High — to illume the darkness and counteract the 
moral abominations and idolatries oi the Pagan world. If the 
predictions of ancient prophets ate to be fulfilled ; if the glorv of 
Jehovah is to cover the earth ; if"ihj isles afar off," that have 
not yet heard of the fame of the Redeemer, nor seen his glory, are 
to be visited with the '• Day-spring from on high," and enrolled 
among the citizens of Zion; if the world is to be regenerated, and 
Righteousness and Praise to spring forth be ore all nations — those 
grand events will be accomplished partly through the influence 
and direction of those celestial luminaries which are placed in the 
firmament to be tor signs, and for seasons, and for days and years. 
The light reflected from the material heavens will lend its aid in 
illuminating the minds of the benighted tribes of mankind, till 
they be prepared lor being transported into those celestial man- 
sions where knowledge shall be perfected, and sovereign power 
triumphant. It will be likewise from aid derived from the heav- 
enly oibs that the desolate wastes of the globe in every region will 
be cultivated and replenished with inhabitants. For the Almighty 
" created not the earth in vain, but formed it to be inhabited ;" and 
Ms purpose in this respect must ultimately be accomplished; and 



INTRODUCTION. XIU 

the process of peopling and cultivation is now going forward in 
New Holland, Van Diemen's Land, Africa, the Western States 
of America, and other regions where sterility and desolation have 
prevailed since the universal Deluge. But how could colonies of 
men be transported from civilized nations to those distant regions, 
unless by the guidance of celestial luminaries, and by the aid of 
those arts which are founded on the observations of astronomy *? 
So that this science exerts an extensive and beneficial influence 
over the most important affairs of mankind. 

In short, astronomy, by unfolding to us the causes of certain 
celestial phenomena, has tended to 

DISSIPATE SUPERSTITIOUS NOTIONS 

and vain alarms. In former ages the approach of a blazing comet, 
or a total eclipse of the sun or moon, were regarded with universal 
consternation as prognostics of impending calamities, and as har- 
bingers of Divine vengeance. And even in the present day, such 
notions prevail among most of those nations and tribes that are 
unacquainted with astronomical science. During the darkness 
occasioned by a solar eclipse, the lower orders of Turkey have 
been seen assembling in clusters in the streets, gazing wildly at 
the sun, running about in wild distraction, and firing volleys of 
muskets at the sun to frighten away the monster by which they 
supposed it was about to be devoured. The Moorish song of" 
death, or the howl they make for the dead, has been heard, on 
such occasions, resounding from the mountains and the vales, 
while the wumen brought into the streets all the brass pans, and 
vessels, and iron utensils they could collect, and sinking them with 
all their force, and uttering dreadful screams, occasioned a horrid 
noise that was heard for miles around. But astronomy has put to 
flight such terrific phantoms and groundless alarms, by unfolding 
to us the true causes of all such phenomena, and showing us that 
they happen in exact conformity with those invariable laws by 
which the Almighty conducts the machine cf the universe — that 
eclipses are merely the effects of the shadow of one opaque globe 
falling upon another, and that comets are bodies which move in 
regular, but long elliptical orbits — which appear and disappear in 
stated periods of time, and are destined to subserve some grand 
and beneficent designs in the system to which they belong. So 
that we may now contemplate all such celestial phenomena, not 
only with composure and tranquillity, but with exultation and de- 
light. In short, astronomy has undermined the absurd and falla- 
cious notions by which the professors of Judicial Astrology have 
attempted to impose on the credulity of mankind, under pretence 
of disclosing the designs of Fate, and the events of futurity. It 
shows us, that the stars are placed at immeasurable distances 
from our terrestrial sphere — that they can have no influence upon 
the earth, but what arises from the law of universal gravitation — 
that the great end for which they were created was to diffuse light, 
and to perform other important services in regions intinitely dis- 
tinct from the sphere we occupy — that the planets are bodies of 
different sizes, and somewhat si in lar to the globe oa which we 



XIV INTRODUCTION. 

live — that all their aspects and conjunctions are the result of phy- 
sical laws which are regular and immutable — and that no data 
can be ascertained on which it can be proved that they exert a 
moral influence on the temperaments and destinies of men, except 
in so far as they tend to raise our affections to their Almighty 
Author, and excite us to confide in his care, and to contemplate 
the effects of his wisdom and omnipotence. The heavens are set 
before us, not as the " Book of Fate," in which we may pry into 
Uie secrets of our future destiny, which would only serve to de- 
stroy activity, and increase the pressure of our present afflictions — 
Dut as the " Book of God," in which we may read his wondrous 
works, contemplate the glory of his eternal empire, and be excited 
to extend. our views to those expansive scenes of endless felicity 
which await the faithful in the realms above. 

Independently of the considerations above stated, the study of 
astronomy is attended with many advantages in a moral, intel- 
lectual, and religious point of view. 

1. This department of science unfolds to us the most striking dis- 
plays of the 'perfections of the Deity — particularly the grandeur of 
his Omnipotence. His Wisdom is conspicuously displayed in the 
general arrangement of the heavenly orbs, particularly in refer- 
ence to f he globes which compose the solar system— in placing 
near the center of this system that immense luminary the Sun, 
from whence light and heat might be distributed, in due propor- 
tion, to all the worlds that roll around it — in nicely proportioning 
the motions and distances of all the planets, primary and second- 
ary — in uniting them in one harmonious system, by one grand 
universal law which prevents them from flying off in wild confu- 
sion through the infinity of space — in the constancy and regularity 
of their motions, no one interfering with another, or deviating 
from the course prescribed — in the exactness with which they run 
their destined rounds, finishing their circuits with so much ac- 
curacy as not to deviate from their periods of revolution the hun- 
dredth part of a minute in a thousand years — in the spherical 
figures given to all those mighty orbs, and the diurnal motions 
impressed upon them, by which a due proportion of light and heat 
is diffused over every part of their surface. The Benevolence of 
the Deity shines no less conspicuous in those upper regions, in 
ordering all the movements and arrangements of the celestial 
globes so as to act in subserviency to the comfort and happiness 
of sentient and intelligent beings. For, the wisdom of God is 
never employed in devising means without an end; and the grand 
end of all his arrangements, in so far as our views extend, is the 
communication of happiness ; and it would be inconsistent with 
the wisdom and other perfections of God not to admit, that the 
same end is kept in view in every part of his dominions, however 
far remo/ed from the sphere of oar contemplation. The heavens, 
therefore, must be considered as presenting a boundless scene of 
Divine benevolence. For they unfold to view a countless number 
of magnificent globes, calculated to be the habitations of various 
orders of beings, and which are, doubtless, destined to be the 
abodes of intellectual life. For the character of the Deity would 
be impeached, and his wisdom virtually denied, were we to sup- 



INTRODUCTION. XV 

pose him to arrange and establish a magnificent series of means 
without an end corresponding, in utility and dignity, to the gran- 
deur of the contrivance. When, therefore, we consider the innu- 
merable worlds which must exist throughout the immensity of 
space, the countless myriads of intelligences that people them, the 
various ranks and orders of intellect that may exist among them, 
the innumerable diversified arrangements which are made for 
promoting their enjoyment, and the peculiar displays of Divine 
benignity enjoyed in every world — we are presented with a scene 
of Divine goodness and beneficence which overpowers our con- 
ceptions, and throws completely into the shade all that we perceive 
or enjoy within the confines of this sublunary world. And, al- 
though "the minute displays of Divine benevolence in distant 
worlds are not yet particularly unfolded to our view, yet this cir- 
cumstance does not prove that no such displays exist; — and as we 
are destined to an immortal life in another region of creation, we 
shall, doubtless, be favored with a more expansive view of the 
effects of Divine benignity in that eternal scene which lies be- 
fore us.-- ' ■' 

But this science exhibits a more striking display than any other 
of the Omnipotent energies of the Eternal Mind. It presents before 
us objects of overpowering magnitude and splendor — planetary 
globes a thousand times larger than the earth — magnificent rings 
which would nearly reach from the earth to the moon, and would 
inclose within their vast circumference 500 worlds as large as 
ours — suns a million times larger than this earthly ball, diffusing 
their light over distant worlds — and these suns scattered in every 
direction through the immensity of space, at immeasurable dis- 
tances from each other, and in multitudes of groups which no man 
can number; presenting to the eye and the imagination a per- 
spective of starry systems, boundless as immensity, it presents to 
our view motions so astonishing as to overpower and almost ter- 
rify the imagination — bodies a thousand times larger than the 
earth flying with a velocity of 29,000 miles an hour, performing 
circuits more than three thousand millions of miles in ciicumfer- 
ence, and carrying along with them a retinue of revolving worlds 
in their swift career ; nay, motions, at the rate of 880,000 miles 
an hour, have been perceived among the celestial orbs, which as 
far surpass the motions we behold around us in this lower world, 
as the heavens in height surpass the earth. Such motions are 
perceived not only in the solar system, but in the most distant re- 
gions of the universe, among double stars — they are regular and 
uninterrupted — they have been going forvard for thousands, per- 
haps for millions of years — there is perhaps no body in the uni- 
verse but is running i:s round with similar velocity ; and it is not 
unlikely that the whole machine of universal nature is in per- 
petual motion amidst the spaces of immensity, and will continue 
thus to move throughout all the periods of endless duration. Such 
objects and such motions evidently display the omnipotence of the 
Creator beyond every other scene which creation presents; and, 
when seriously contemplated, cannot but inspire us with the most 
lofty and impressive conceptions of the "eternal power" and ma- 
jesty of Him who sits on the throne ol the universe, and by whom 






XVI INTRODUCTION. 

all its mighty movements are conducted. They demonstrate, that 
his agency is universal and uncontrollable — that he is able to ac- 
complish all his designs, however incomprehensible to mortals — 
that no created being can frustrate his purposes, and that he is 
worthy of our highest affection, and our incessant adoration. 

"1. Astronomy displays before us the extent and grandeur of God's 
universal empire. The globe we inhabit, with all its appendages, 
torms a portion, of the Divine empire, and, when minutely investi- 
gated, exhibits a striking display of its Creator's power, benignity, 
and intelligence. But it forms only one small province of his uni- 
versal dominions — an almost undistinguishable speck in the great 
map of the universe : and if we confine our views solely to the 
limits of this terrestrial ball, and the events which have taken 
place en its surface, we must form a very mean and circumscribed 
idea of the extent of the Creator's kingdom and the range of his 
moral government. But the discoveries of astronomy have ex- 
tended our views to other provinces of the empire of Omnipotence, 
far more spacious and magnificent. They demonstrate, that this 
earth, with all its vast oceans and mighty continents, and numer- 
ous population, ranks among the smaller provinces of this em- 
pire — that the globes composing the system to which ii belongs, 
(without including the sun,) contain an extent of territory more 
than two thousand times larger than our world — that the sun 
himself is more than 500 times larger than the whole, and 
that, although they were all at this moment buried in oblivion, 
they would scarcely be missed by an eye that could survey the 
whole range of creation. They demonstrate, that ten thousands 
of suns, and ten thousand times ten thousands of revolving worlds, 
are dispersed throughout every region of boundless space, dis- 
playing the creating and supporting energies of Omnipotence; 
and consequently, are all under the care and superintendence of 
Him " who doeth according to his will in the armies of heaven, 
and among the inhabitants of the earth." Such an empire, and 
such only, appears corresponding to the perfections of Him who 
has existed from eternity past, whose power is irresistible, whose 
goodness is unbounded, and whose presence fills the immensity of 
space; and it leads us to entertain the most exalted sentiments of 
admiration at the infinite intelligence implied in the superintendence 
of such vast dominions, and at the boundless beneficence displayed 
among the countless myriads of sensitive and intellectual beings 
which must people his wide domains. 

3. The objects which this science discloses, afford subjects of 
sublime contemplation, and tend to derate the soul above vicious pas- 
sions and groveling pursuits. In the hours of retirement and soli- 
tude what can be more delightful, than to wing our way in imagi- 
nation amidst the splendid objects which the firmament displays 
—to take our flight along with the planets in their wide career — 
to behold them running their ample rounds with velocities forty 
times swifter than a cannon ball — to survey the assemblages of 
their moons, revolving around them in their respectives orders, 
and carried at ilie same time, along with their primaries, through 
the depths of space — to contemplate the magnificent arches which 
adorn the firmament of Saturn, whirling round that planet at the 



INTRODUCTION. XV11 

rate of a thousand miles in a minute, and displaying their radi- 
ance and majestic movements to an admiring population — to add 
scene to scene, ana magnitude to magnitude, till the mind acquire 
an ample conception of such august objects — to dive into the 
depths of infinite space till we be surrounded with myriads of suns 
and systems of worlds, extending beyond the range of mortal com- 
prehension, and all running their appointed rounds, and accom- 
plishing the designs of beneficence in obedience to the mandate of 
their Almighty Author 1 Such objects afford matter for rational 
conversation, and for the most elevated contemplation. In this 
ample field the most luxuriant imagination may range at large, 
representing scenes and objects in endless variety and extent ; and, 
after its boldest excursions, it can scarcely go beyond the reality 
of the magnificent objects which exist within the range of creating 
power and intelligence. 

The frequent contemplation of such objects tends to enlarge the 
capacity of the mind, to ennoble the human faculties, and raise the 
soul above groveling affections and vicious pursuits. For the 
dispositions of mankind and their active pursuits generally cor- 
respond to the train of thought in which they most frequently in- 
dulge. If these thoughts run among puerile and vicious objects, 
such will be the general character of their affections and conduct. 
If their train of thinking take a more elevated range, the train of 
their actions, and the passions they display, will, in some measure, 
be correspondent. 

Can we suppose, that a man whose mind is daily conversant 
with the noble and expansive objects to which I have adverted, 
would have his soul absorbed in the pursuits of ambition, tyranny, 
oppression, war, and devastation 1 

Would he rush like a madman through burning cities, and 
mangled carcasses of the slain, in order to trample underfoot the 
rights of mankind, and enjoy a proud pre-eminence over his fel- 
lows — and find pleasure in such accursed pursuits 1 

Would he fawn on statesmen and princes, and violate every 
moral principle, in order to obtain a pension, or a post of opulence 
or honor 1 Would he drag his fellow-men to the stake, because 
they worshiped God according to the dictates of their consciences, 
and behold with pleasure their bodies roasting in the flames 1 

Would he drive men, women, and children from their homes, 
loaded with chains and fetters, to pine in misery and to perish in 
a distant land, merely because they asserted the rights to which 
they were entitled as citizens and as rational beings 1 

Or, would he degrade himself below the level of the brutes by ? 
daily indulgence in rioting and drunkenness, till his faculties were 
benumbed, and his body found wallowing in the mire 1 

It is scarcely possible to suppose that such passions and conduct 
would be displayed by the man who is habitually engaged in 
celestial contemplations, and whose mind is iamiliar with the 
august objects which the firmament displays. " If men were 
taught to act in view of all the bright worlds which are loukin^ 
down upon them, they could not be guilty of those abominable 
cruelties" which some scenes so mournfully display; We shou 
then expect, that the iron rod of oppression would be broken ift 
2* 



XV111 INTRODUCTION. 

pieces — that war would cease its horrors and devastations — that 
liberty would be proclaimed to the captives — that "righteousness 
would run down our streets as a river," and a spirit congenial to 
that of the inhabitants of heaven would be displayed by the rulers 
ot nations, and by all the families of the earth. For all the scenes 
which the firmament exhibits have a tendency to inspire tran- 
quillity — to produce a love of harmony and order, to stain the pride 
of human grandeur — to display the riches of Divine beneficence — to 
excite admiration and reverence — and to raise the soul to God as the 
Supreme Director of universal nature, and the source and center 
of all true enjoyment ; — and such sentiments and affections are 
directly opposed to the degrading pursuits and passions which 
have contaminated the society of our world, and entailed misery 
on our species. 

I might have added, on this head, that the study of this subject 
has a peculiar tendency to sharpen and invigorate the mental fac- 
ulties. It requires a considerable share of attention and of intel- 
lectual acumen to enter into all the particulars connected with the 
principles and facts of astronomical science. The elliptical form 
of the planetary orbits, and the anomalies thence arising, the 
mutation of the earth's axis, the causes of the seasons, the diffi- 
culty of reconcilingahe apparent motions of the planets with their 
real motions in circular or elliptical orbits, the effects produced 
by centrifugal and centripetal forces, the precession of the equi- 
noxes, the aberration of light, the method of determining the dis- 
tances and magnitudes of the celestial bodies, mean and apparent 
time, the irregularity of the moon's motion, the difficulty ot form- 
ing adequate ideas of the immense spaces in which the heavenly 
bodies move, and their enormous size, and various other particu- 
lars, are apt, at first view, to startle and embarrass the mind, as 
if they were beyond the reach of its comprehension. But, when 
this science is imparted to the young under the guidance of en- 
lightened instructors — when they are shown not merely pictures, 
globes and orreries, but directed to observe with their own eyes, 
and with the assistance of telescopes, all the interesting phenomena 
of the heavens, and the motions which appear, whether real or 
apparent — when they are shown the spots of the sun. the moons 
and belts of Jupiter, the phases of Venus, the rings of Saturn, and 
the mountains and vales which diversify the surface of the moon — 
such objects tend to awaken the attention, to expand the faculties, 
t > produce a taste for rational investigation, and to excite them to 
more eager and diligent inquiries into the subject. The objects 
appear so grand and novel, and strike the senses with so much 
force and pleasure, that the mind is irresistibly led to exert all its 
energies in those investigations and observations by which it 
may be enabled to grasp all the principles and facts of the science. 
And every difficulty which is surmounted adds a new stimulus to 
the exertions of the intellect, urges it forward with delight in the 
path of improvement, and thus invigorates the mental powers, 
and prepares them for engaging with spirit and alacrity in every 
other investigation. 

4. The study of astronomy has a tendency to moderate the pride 
Of man, and to promote humility. Pride is one of the distinguishing 



INTRODUCTION. XIX 

characteristics of puny man, and has been one of the chief causes 
of all the contentions, wars, devastations, oppressions, systems of 
slavery, despotisms, and ambitious projects which have desolated 
and demoralized our sinful world. Yet there is no disposition 
more incongruous to the character and circumstances of man. 
Perhaps there are no rational beings throughout the universe 
among whom pride would appear more unseemly or incompatible 
than in man ; considering the abject situation in which he is 
placed. He is exposed to innumerable degradations and calami- 
ties, to the rage of storms and tempests, the devastations of earth- 
quakes and volcanoes, the fury of whirlwinds, and the tempestuous 
billows of the ocean, the ravages of the sword, pestilence, famine, 
and numerous diseases, and, at length, he must sink into the 
grave, and his body become the companion of worms. The most 
dignified and haughty of the sons of men are liable to such degra- 
dations, and are frequently dependent on the meanest fellow- 
creatures whom they despise, for the greater part of their accom- 
modations and comforts. Yet. in such circumstances, man, that 
puny worm of the dust, whose knowledge is so limited, whose 
follies are so numerous and glaring — has the effrontery to strut in 
all the haughtiness of pride, and to glory in his shame. When 
scriptural arguments and motives produce little effect, I know no 
considerations which have a more powerful tendency to counteract 
this deplorable propensity of human beings than those which are 
borrowed from the objects connected with astronomy. They show 
us what an insignificant being — what a mere atom, indeed, man 
appears amidst the immensity of creation. What is the wmole of 
this globe, compared with the solar system, which contains a 
mass of matter ten hundred thousand times greater 1 What is it 
in comparison of the hundred millions of suns and worlds which 
the telescope has descried throughout the starry regions, or of that 
infinity of worlds which doubtless lie beyond the range of human 
vision in the unexplored regions of immensity 1 What, then, is a 
kingdom, or a province, or a baronial territory, of which we are 
as proud as if we were the lords of the universe, and for which 
we engage in so much devastation and carnage 1 What are they 
when set in competition with the glories of the sky 1 Could we 
take our station on the lofty pinnacles of heaven, and look down 
on this scarcely distinguishable speck of earth, we should be ready 
to exclaim with Seneca, " Is it to this little spot that the great de- 
signs and vast desires of men are confined? Is it for this there is 
so much disturbance of nations, so much carnage, and so many 
ruinous wars 1 O folly of deceived men, to imagine great king 
doms in the compass of an atom, to raise armies to divide a point 
of earth with the sword !" It is unworthy of the dignity of an im- 
mortal mind to have its affections absorbed in the vanishing 
fplendors of earthly grandeur, and to feel proud of the paltry pos- 
sessions and distinctions of this sublunary scene. To foster a 
spirit of pride and vain-glory in the presence of Him who " sitteth 
on the circle of the heavens," and in the view of the overwhelming 
grandeur and immensity of his works, is a species of presumption 
and arrogance of which every rational mind ought to feel asham- 
ed. And, therefore, we have reason to believe, that those multi- 



XX INTRODUCTION. 

tudes of fools, " dressed in a little brief authority," who walk in 
all the loftiness of pride, have not yet considered the rank they 
hold in the scale of universal being ; and that a serious contem- 
plation of the immensity of creation would have a tendency to 
convince us of our ignorance and nothingness, and to humble us 
in the dust, in the presence of the Former and Preserver of all 
worlds. We have reason to believe that the most exalted beings 
in the universe — those who are furnished with the most capacious 
powers, and who have arrived at the greatest perfection in know- 
ledge — are distinguished by a proportional, share of humility ; for, 
in proportion as they advance in their surveys of the universal 
kingdom of Jehovah, the more will they feel their comparative 
ignorance, and be convinced of their limited faculties, and of the 
infinity of objects and operations which lie beyond their ken. At 
the same time they will feel, that all the faculties they possess 
were derived from Him w r ho is the original fountain of existence, 
and are continually dependent for their exercise on his sustaining 
energy. Hence we find, that the angelic tribes are eminently 
distinguished for the exercise of this heavenly virtue. They 
" cover their faces with their wings " in the presence of their 
Sovereign, and fly, with cheerfulness, at his command, to our de- 
graded world, " to minister to the heirs uf salvation." It is only 
in those worlds where ignorance and depravity prevail (if there be 
any such besides our own) that such a principle as pride is known 
or cherished in the breast of a dependent creature — and therefore 
every one in whom »t predominate s, however high his station or 
worldly accomplishments, or however abject his condition may be, 
must be considered as either ignorant or depraved, or more prop- 
erly, as having both those evils existing in his constitution, the 
one being the natural and necessary result of the other. 

5. The studies connected with astronomy tend to prepare the 
soul for the employments of the future world. In that world, the 
glory of the Divine perfections, as manifested throughout the 
illimitable tracts of creation, is one of the objects which unceas- 
ingly employ the contemplation of the blessed. For they are 
represented in their adorations as celebrating the attributes of the 
Deity displayed in his operations: "Great and marvelous are 
thy works, Lord God Almighty ! thou art worthy to receive glory 
and honor and power, for thou hast created all things, and for thy 
pleasure they are and were created." Before w r e can enter that 
world and mingle with its inhabitants, we must acquire a rdish 
for their employments, and some acquaintance with the objects 
which form the subject of their sublime investigations ; other- 
wise we could feel no enjoyment in the society of heavenly intel- 
ligences, and the exercises in which they engage. The investiga-i' 
tions connected with astronomy, and the frequent contemplation 
of its objects, have a tendency to prepare us for such celestial em- 
ployments, as they awaken a.ttention to such subjects, as they in- 
vigorate the faculties, and enlarge the capacity of the intellect, as 
they suggest sublime inquiries, and desires fcr further information 
which may afterwards be gratified ; as they form the groundwork 
of the progress we may afterwards make in that state in our sur- 
reys of the Divine operations, and as they habituate the mind to 



INTRODUCTION. XXI 

take large and comprehensive v r iews of the empire and moral 
government of the Almighty. Those who have made progress in 
such studies, under the influence of holy dispositions may be con- 
sidered as fitted to enter heaven with peculiar advantages, as they 
will then be introduced to employments and investigations to 
which they were formerly accustomed, and for which they were 
prepared — in consequence of which they may be prepared for fill- 
ing stations of superior eminence in that world, and for directing 
the views and investigations of their brethren who enjoyed few 
opportunities of instruction and improvement in the present state. 
For we are informed, in the sacred records, that "they who are 
wise," or as the words should be rendered, " they who excel in 
wisdom shall shine as the brightness of the firmament, and they 
that turn many to righteousness, as the stars for ever and ever." 

6. The researches of astronomy demonstrate, that it is in the 
power of the Creator to open to his intelligent offspring endless sources 
of felicity. In looking forward to the scene of our future destina- 
tion, we behold a series of ages rising in succession without any 
prospect of a termination; and, at first view, it might admit of a 
doubt, whether the universe presents a scene so diversified and 
boundless, that intelligent beings, during an endless duration, 
could expect that, new scenes of glory and felicity might be con- 
tinually opening to their view, or, whether the same series of per- 
ceptions and enjoyments might not be reiterated so as to produce 
satiety and indifference. Without attempting positively to decide 
on the particular scenes or sources of happiness that may be 
opened in the eternal world, it may be admitted, that tlie Deity has 
it in his power to gratify his rational creatures, during every period 
of duration, with new objects and new sources of enjoyment ; and, 
that it is the science of astronomy alone which has presented us 
with a demonstration, and a full illustration of this important truth. 
For, it has displayed before us a universe boundless in its extent, 
diversified as to its objects, and infinite as to their number and 
variety. Even within the limits of human vision the number of 
worlds which exist cannot be reckoned less than three thotisa?id 
millions ; and those which are nearest to us, and subject to our 
particular examination, present varieties of different kinds, both 
as to magnitude, motion, splendor, color and diversity of surface — 
evidently indicating, that every world has its peculiar scenes of 
beauty and grandeur. But, as no one will be so presumptuous as 
to assert, that the boundaries of the universe terminate at the 
limits of human vision, there may be an assemblage of creation 
beyond all that is visible to us, which as far exceeds the visible 
system as the vast ocean exceeds in magnitude a single drop of 
water; and this view is nothing more than compatible with the 
idea of a Being whose creating energies are infinite, and whose 
presence fills immensity. Here, then, we have presented to our 
contemplation a boundless scene, corresponding, in variety and 
extent of space, to the ages of an endless duration ; so that we can 
conceive an immortal mind expatiating amidst objects of benig- 
nity, sublimity and grandeur, ever varied and ever new, through- 
out an eternal round of existence, without ever arriving at a point, 
where it might be said, "Hitherto shalt thou come, but n* "' 



XX11 INTRODUCTION. 

ther." And we have reason to conclude that such will be the 
privilege and enjoyment of all holy beings. For we are informed 
on the authority of inspiration, that " in God's presence there is ful- 
ness of joy, and at his right hand are pleasures for evermore. 

7. The science of astronomy is a study which will be prosecuted 
without intermission in the eternal world. This may be inferred 
from what has been already stated, For it is chiefly among the 
numerous worlds dispersed throughout the universe that God is 
seen, his perfections manifested, and the plans of his moral govern- 
ment displayed before the eyes of unnumbered intelligences. The 
heavens constitute by far the grandest and most extensive portion 
of the empire of Omnipotence ; and if it shall be one part of the 
happiness of immortal spirits to behold and investigate tne beauty, 
grandeur and beneficence displayed throughout this empire, we 
may rest assured, that they will be perpetually employed in such 
exercises ; since the objects of their investigation are boundless as 
immensity; — or, in other words, astronomy, among other branches 
of celestial science, will be their unceasing study and pursuit. As 
it has for its object, to investigate the motions, relations, phenome- 
na, scenery, and the ultimate destination of the great bodies of the 
universe, the subject can never be exhausted. Whatever may be 
said in regard to the absolute perfection of other sciences, astrono- 
my can never be said, at any future period of duration, to have 
arrived at perfection, in so far as it is a subject of study to finite 
minds ; and, at this moment, even in the view of the Infinite Mind 
that created the universe, its objects may not yet be completed. 
For we have reason to believe that the work of creation is still 
going forward, and, consequently, chat new worlds and systems 
may be continually emerging from nothing under the energies of 
Creating Power. However capacious, therefore, the intellects of 
good men, in a future world, may be, they will never be able fully 
to explore the extent and variety, " the riches and glory " of Him 
" who dwells in light unapproachable ;" — yea, the most exalted of 
created intelligences, wherever existing, although their mental 
powers and activities were incomparably superior to those of man, 
will be inadequate to a full investigation and comprehension of 
the grandeur and sublimities of that kingdom which exten is 
throughout the regions of immensity. And this circumstance will 
constitute one ingredient of their happiness, and a security for its 
permanency. For, at every period of infinite duration, they will 
be enabled "to look forward to a succession of scenes, objects and 
enjoyments different from all they had previously contemplated or 
experienced, without any prospect of a termination. We may 
therefore conclude, that, unless the material universe be demolish- 
ed, and the activities of immortal minds suspended, the objects of 
astronomy will continue throughout eternity to be the subject of 
study, and of unceasing contemplation. 

Such are some of the advantages attending the study of the 
science of astronomy. It lies at the loundation of our geographi- 
cal knowledge — it serves as a handmaid and director to the trav- 
eler and navigator — it is subservient to the purposes of universal 
commerce — it determines the seasons, and directs the operations 
of the husbandman — it supplies us with an equable standard of 



INTRODUCTION. XX111 

time, and settles the events of history — it lends its aid to the propa- 
gation of religion, and undermines the foundation of superstition 
and astrology. Above all, it illustrates the glory of the perfections 
of the Deity — displays the extent and grandeur of his universal 
empire — affords subjects of sublime contemplation — enlarges the 
conceptions, and invigorates the mental powers — counteracts the 
influence of pride, and promotes the exercise of humility — pre- 
pares the soul for the employments of the future world — and de- 
monstrates, that the Creator has it in his power to open up end- 
lessly diversified sources of happiness to every order of his intelli- 
gent offspring, throughout all the revolutions of eternity. The 
moral advantages arising from the study of this science, however, 
cannot be appreciated or enjoyed, unless such studies and investi- 
gations be prosecuted in connection with the facts and principles 
of Revelation. But, when associated with the study of the Scrip- 
tures, and the character of God therein delineated, and the practice 
of Christian precepts, they are calculated " to make the man of 
God perfect," to enlarge his conceptions of Divine perfection, and 
to expand his views of " the inheritance of the saints in light." 

Such being the advantages to be derived from the study of this, 
science, it ought to form a subject of attention in every seminary 
intended for the mental and moral improvement of mankind. In 
order to the improvement of the young in this science, and that its 
objects may make a deep impression on their minds, they should 
be directed to make frequent observations, as opportunity offers, on 
the movements of the nocturnal heavens, and to ascertain all the 
facts which are obvious to the eye of an attentive spectator. And. 
while they mark the different constellations, the apparent diurnal 
motion of the celestial vault, the planets in their several courses, 
and the moon walking in her brightness among the host of stai.s— 
they should be indulged with views of the rings of Saturn, the belts 
and satellites of Jupiter, the phases of Mercury and Venus, the 
numerous groups of stars in the Milky Way, the double and treble 
stars, the most remarkable Nebula, the mountains and plains, the 
caverns and circular ridges of hills which diversify the surface of 
the moon, as they appear though good achromatic or reflecting 
telescopes. Without actual observation, and the exhibition of 
such interesting objects, the science of astronomy makes, compara- 
tively, little impression On the mind. Our school books on ;.<s- 
tronomy should be popular in their language and illustrations. 
but, at the same time, they should be comprehensive in their details, 
and every exhibition should be clear and well defined. They 
should contain, not merely descriptions of facts, to be received on 
the authority of the author or the instructor, but illustrations of 
the reasons or arguments on which the conclusions of astronomy 
are founded, and of the modes by which they have been ascer- 
tained. And, while planetan'ums, celestial globes, and plani- 
spheres of the heavens are exhibited, care should be taken to di- 
rect the observations of the pupils as frequently as possible to the 
objects themselves, and to guard them against the limited and dis- 
torted notions which all kinds of artificial representations have a 
tendency to convey. 

There is still room for improvement in all the iaiUtory books 



XXIV INTRODUCTION. 

on this subject, I have examined ; but such books are now rapidly 
improving, both as to their general plan, and the interesting na- 
ture of their details. I have seen nothing superior in this respect, 
or better adapted to the purpose of rational instruction, than Mr. 
Burritt's excellent work entitled, "The Geography of the Heav- 
ens," second edition, comprising 342 closely printed pages. It 
contains, in the first place, a full and interesting description of all 
the constellations, and principal stars in the heavens, interspersed 
with a great variety of mythological, historical and philosophical 
information, calculated to 'amuse and instruct the general reader, 
and to arrest the attention of the young. The descriptions of the 
bodies connected with the solar system are both popular and 
scientific, containing a lucid exhibition of the facts which have 
been ascertained respecting them, and a rational explanation of 
the phenomena connected with their various aspects and motions. 
The Celestial Alias which accompanies the work is varied, com- 
prehensive, and judiciously constructed, and forms the most com- 
plete set of planispheres, lor the purpose of teaching, which has 
hitherto been published. It consists of four maps about fourteen 
inches square, delineated on the same principles as geographical 
projections, exhibiting the stars that pass near the meridian at a 
certain hour, along with the circumjacent constellations for ev- 
ery month, and for every day of the year. Besides these there 
are two circumpolar maps of the northern and southern hemi- 
spheres of the heavens, and a planisphere on the principle of 
Mercator's projection, which exhibits at one view the sphere of 
the heavens, and the relative positions of the different constella- 
tions and principal stars. "With the assistance of these maps, 
which in a great measure supersede the use of a celestial globe, an 
intelligent teacher may, at certain intervals in the course of a 
year, render his pupils familiar with most of the visible stars in 
the heavens: and they will make a deeper impression on their 
minds when taught in this way, than by the use of a globe. This 
work, on the whole, indicates great industry and research on the 
part of the author, and a familiar acquaintance with the various 
departments of the science of the heavens. He has derived his 
materials from the most valuable and modern works of science, 
and has introduced not a few illustrations and calculations of his 
own, which tend to enhance the general utility of the work. The 
moral and religious reflections which the objects of this science 
natu ally suggest, have not been overlooked, and, I trust, will have 
a tendency to raise the minds of the young to that Almighty Be- 
ing, whose power, wisdom, and superintending providence are so 
strikingly displayed throughou the regions of the firmament. 



PRELIMINARY CHAPTER. 

In entering upon this study, the phenomena of the heavens, 
as they appear in a clear evening, are the first objects that 
demand our attention. Our first step is to learn the names 
and positions of the heavenly bodies, so that we can identify, 
and distinguish them from each other. 

In this manner, they were observed and studied ages be- 
fore books were written, and it was only after many, careful 
and repeated observations, that systems and theories of As- 
tronomy were formed. To the visible heavens, then, the at- 
tention of the pupil should be first directed, for it is only when 
he shall have become, in some measure, familiar with them, 
that he will be able to locate his Astronomical knowledge, or 
fully comprehend the terms of the science. 

For the sake of convenient reference, the heaven's were 
early divided into constellations, and particular names assign- 
ed to the constellations and to the stars which they contain. 
A constellation may be defined to be a cluster or group of 
stars embraced in the outline of some figure. These figures 
are, in many cases, creations of the imagination ; but in others, 
the stars are in reality so arranged as to form figures which 
have some resemblance to the objects whose names have 
been assigned to them. 

These divisions of the celestial sphere bear a striking analogy to the civil divi- 
sions of the globe. The constellations answer to states and kingdoms, the most 
brilliant clusters to towns and cities, and the number of stars in each, to their 
respective population. The pupil can trace the boundaries of any constellation, 
and name all its stars, one by one, as readily as he can trace the boundaries of 
a state, or name the towns and cities from a map of New England- In this sense, 
there may be truly said to be a Geography of the Heavens. 

The stars are considered as forming, with reference to their 
magnitudes, six classes; the brightest being called stars of 
the first magnitude, the next brightest, stars of the second 
magnitude, and so on to the sixth class, which consists of the 
smallest stars visible to the naked eye. In order to be able 

Why, in entering upon the study of Astronomy, shotiJd the attention of the pupil be 
first directed to the vi-ible heavens? Why were the heavens early divided into con- 
stc ations, and names assigned to the constellations and the stars? What i<a con- 
stellation? Do these figures really exist in the skies ? In to fiat seme, may there truly 
besaid to be a Geography of the. Heavens? How many classes are the stcrs considered 
as forming with reference to their magnitude i 

3 



26 PRELIMINARY CHAPTER. 

to designate, with precision their situations, imaginary circles 
have been considered as drawn in the heavens, most of which 
correspond to and are in the same plane with similar circles, 
supposed, for similar purposes, to be drawn on the surface 
of the Earth. 

In order to facilitate the study of it, artificial representa- 
tions of the heavens, similar to those of the surface of the 
Earth, have been made. Thus, a Celestial Atlas composed of 
several maps, accompanies this work. Before, however, pro- 
ceeding to explain its use, it is necessary to make the pupil 
acquainted with the imaginary circles alluded to above. 

Circles of the Sphere. — The Axis of the Earth is an 
imaginary line, passing through its center, north and south, 
about which its diurnal revolution is performed. 

The Poles of the Earth are the extremities of its axis. 

The Axis of the Heavens is the axis of the Earth produc- 
ed both ways to the concave surface of the heavens. 

The Poles of the Heavens are the extremities of their axis. 

The Equator of the Earth is an imaginary great circle 
passing round the Earth, east and west, every where equally 
distant from the poles, and dividing it into northern and 
southern hemispheres. 

The Equator of the Heavens, or Equinoctial, is the great 
circle formed on the concave surface of the heavens, by pro- 
ducing the plane of the Earth's equator. 

A plane is that which has surface but not thickness. The plane of a circle is 
that imaginary superficies which is bounded by the circle. 

The Rational Horizon is an imaginary great circle, whose 
plane, passing through the center of the Earth, divides the 
heavens into two hemispheres, of which the upper one is 
called the visible hemisphere, and the lower one, the invisi- 
ble hemisphere. It is the plane of this circle which deter- 
mines the rising and setting of the heavenly bodies. 

The Sensible or Apparent Horizon, is the circle which 
terminates our view, where the Earth and sky appear to meet. 

To a person standing on a plain, this circle is but a few miles in diameter. If 
the eye be elevated five feet, the radius of the sensible horizon will be less than 
two miles and three quarters ; if the eye be elevated six feet, it will be just three 
miles. The observer being always in the center of the sensible horizon, it will 
move as he moves, and enlarge or contract, as his station is elevated or depressed. 



"What expedient has been devised for desisrnating, with precision, the situations of 
the heavenly bodies :< What is the axis of the Earth ! What are the poles oi the Earth? 
What is the axis of the heavens ) What are the poles of the heavens ? What is the 
equator of the Earth ? "What is the equator of the heavens or the equinoctial ? What 
is a plane? What is the plane of a cirae? What is the rational horizon 1 What ia 
the sensible or apparent horizon f What is the diameter of this circle to a ,Jtr~<on stand- 
ing on a plain 3 What will its radius be if the eye be eb rated five feet I If it bt *£+ 
voted six feet 7 On ichat does the place of its center and its circumference depend 



PRELIMINARY CHAPTER. 27 

The Poles of the Horizon are two points, of which the one 
is directly overhead, and is called the Zenith ; the other is 
directly underfoot, and is called the Nadir. 

Vertical Circles are circles drawn through the Zenith and 
Nadir of any place, cutting the horizon at right angles. 

The Prime Vertical is that which passes through the east 
and west points of the horizon. 

The Ecliptic is the great circle which the S an appears to 
describe annually among the stars. It crosses the Equinoc- 
tial, a little obliquely, in two opposite points which are called 
the Equinoxes. The Sun rises in one of these points on the 
21st of March; this point is called the Vernal Equinox. It 
sets in the opposite point on the 23d of September ; this point 
is called the Autumnal Equinox. One half of the Ecliptic lies 
on the north side of the Equinoctial, the other half on the 
south side, making an angle with it of 23^°. This angle is 
called the obliquity of the Ecliptic. The axis of the Eclip- 
tic makes the same angle with the axis of the heavens ; so 
that the poles of each are 23£° apart. 

This angle is perpetually decreasing. At the commencement of the Christian 
era, it was about 23° 45'. At the beginning of 1836. it was only 23° 27' 33", show- 
ing an annual diminution of about half a second, or 45".70 in a hundred years. 
A lime will arrive, however, when this angle, having reached its minimum, will 
again increase in the same ratio that it had before diminished, and thus it will 
continue to oscillate at long periods, between certain limits, which are said to be 
comprised within the space of 20° 42'. 

The Ecliptic, like every other circle, contains 360°, and it Is 
divided into 12 equal arcs of 30° each, called signs, which the 
ancients distinguished by particular names. This division 
commences at the vernal equinox, and is continued east- 
wardly round to the same point again, in the following order : 
Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scor- 
pio, Sagittarius, Capricovnus, Aquarius, Pisces The Sun, 
commencing at the first degree of Aries, about the 21st of 
March, passes, at a mean rate, through one sign every month. 

The Zodiac is a zone or girdle, about 16 degrees in 
breadth, extending quite round the heavens, and including 
all the heavenly bodies within 8° on each side of the ecliptic. 
It includes, also, the orbits of all the planets, except some of 
the asteroids, since they are never seen beyond S° either 
north or south of the ecliptic. 

Parallels of Latitude are small circles imagined to be 



What are the poles of the horizon? "What are vertical circles? What is the prime 
vertical ? What is the ecliptic ? What are the equinoxes? The vernal equinox ? The 
autumnal equinox ? How is the ecliptic situated with respect to the equinoctial ? What 
is the obliquity of the ecliptic ? Describe the manner in tchich this angle varies. De- 
scribe the division of the ecliptic into signs. How much, at a mean rate, does the Sm 
advance in the ecliptic every month 1 What is the zutUsc 1 What are parallels of la- 
titude ; 



28 PRELIMINARY CHAPTER. 

drawn on the Earth's surface, north and soath of the equator, 
and parallel to it. 

Parallels of Declination are small circles, imagined to 
be drawn on the concave surface of the heavens, north and 
south of the equinoctial, and parallel to it ; or they may be 
considered as circles formed by producing the parallels of 
latitude to the heavens. 

The Tropic of Cancer is a small circle, which lies 23i° 
north of the Equinoctial, and parallel to it. The Tropic of 
Capricorn is a small circle, which lies 23£° south of the equi- 
noctial, and parallel to it. On the celestial sphere, these 
two circles mark the limits of the Sun's farthest declination 
north and south. On the terrestrial sphere, they divide the 
torrid from the two temperate zones. That point in the 
ecliptic which touches the tropic of Cancer, is called the 
Summer Solstice; and that point in the ecliptic which touch- 
es the tropic of Capricorn, is called the Winter Solstice. 

The distance of these two points from the equinoctial, is always equal to the 
obliquity of the ecliptic, which, in round numbers, is 23c° ; but as we have seen 
the obliquity of the ecliptic is continually changing ; therefore the position of the 
tropics must make a correspondent change. 

The Colures are two great circles which pass through the 
poles of the heavens, dividing the ecliptic into four equal 
parts, and mark the seasons of the year. One of them passes 
through the equinoxes at Aries and Libra, and is thence 
called the Equinoctial Colure ; the other passes through the 
solstitial points or the points of the Sun's greatest declination 
north and south, and is thence called the Solstitial Colure. 

The Sun is in the equinoctial points the 21st of March and the 23d of Septem- 
ber. He is in the solstitial points the 22d of June and the 22d of December. 

The Polar Circles are two small circles, each about 66j° 
from the equator, being always at the same distance from the 
poles that the tropics are from the equator. The northern 
is called the Arctic circle, and the southern the Antarctic 
circle. 

Meridians are imaginary great circles drawn through the 
poles of the world, cutting the equator and the equinoctial 
at right angles. 

Every place on the Earth, and every corresponding point in the heavens, is 
considered as having a meridian passing through it; although astronomers apply 

What are parallels of declination ? What is the Tropic of Cancer f What is the Tropic 
of Capricorn? What is the summer solstice ? What is the winter solstice? What is 
their distance from the ejuator, compared with the obliquity of the. ecliptic? Is this dis- 
tance always the name? What are the colures? What is the equinoctial colure? 
What is the solstitial colure? On what days of the year is the sun in the equinoctial 
points ? On what days is he in the solstitial points ? What are the polar circles ? By 
what names are they distinguished ' What are meridians ? ll'>to 7>iany meridians 
•re there) How many do astronomers apply to the fieavens? 



PRELIMINARY CHAPTER. 29 

bat 24 to the heavens, thus dividing the whole concave surface into 24 sections, 
each 15° in width. These meridians mark the space which the heavenly bodies 
appear to describe, every hour, for the 24 hours of the day. They are thence 
sometimes denominated Hour Circles. 

In measuring distances and determining positions on the Earth, the equator 
and some fixed meridian, as that of Greenwich, contain the primary starting 
points ; in the heavens, these points are in the ecliptic, the equinoctial, and that 
great meridian which passes through the first point of Aries, called the equinoc- 
tial colure. 

Latitude on the Earth, is distance north or south of the 
equator, and is measured on the meridian. 

Latitude in the Heavens, is distance north or south of the 
ecliptic, and at right angles with it. 

Longitude on the Earth, is distance either east or west 
from some fixed meridian, measured on the equator. 

Longitude in the Heavens, is distance east from the first 
point of Aries, measured on the ecliptic. 

Declination is the distance of a heavenly body either north 
or south of the equinoctial, measured on a meridian. 

Right Ascension is the distance of a heavenly body east 
fromlhe first point of Aries, measured on the equinoctial. 

It is more convenient to describe the situation of the heavenly bodies by their 
declination and right ascension, thau by their latitude and longitude, since the 
former corresponds to terrestrial latitude and longitude. 

Latitude and declination may extend 90° and no more. Terrestrial longitude 
may extend ISO either east or westj but celestial longitude and right ascension, 
being reckoned in only one direction, extend entirely round the circle, or 360°. 

In consequence of the Earth's motion eastward in its orbit, 
the stars seem to have a motion westward, besides their 
apparent diurnal motion caused by the Earih's revolution on 
its axis ; so that they rise and set sooner every succeeding 
day by about four minutes, than they did on the preceding 
This is called their daily acceleration. It amounts to jusi 
two hours a month. 

Example.— Those stars and constellations which do not rise until 10 o'clock 
this evening, will, at the same hour, one month hence, be 30° above the horizon ; 
and, for the same reason, those stars which we see directly overhead' this eve- 
ning, will at the same hour, three months hence, be seen setting in the west; 
having in this time, performed one fourth of their apparent annual revolution. 

The following table of sidereal revolutions, shows the difference between solar 
and sidereal time. The first column contains the numbers of complete revolu- 
tions of the stars, or of the Earth's rotation on its axis ; the second exhibits the 
times in which these revolutions are made ; and the third, shows how much 
the stars gain on the Sun every day — that is, how much sooner they rise and come 
to the meridian every succeeding clay, than they did on the preceding. 

Into how many sections do these meridians divide the concave surface of the hea- 
vtnst Of what width are these sections ? Why are these meridians sometimes called 
hour circles ? In measuring distances on the Earth, what circles contain t/ie primary 
starting points? Where are. these points in measuring distances in the heavejis? 
What is latitude on the Earth ? What is latitude in the heavens ? What is longitude 
on the Earth? What is lonsitude in the heavens? What is declination ? What is 
right ascension ? Why is it 'more convenient to describe the situation of the heavenly 
bodies by their declination and right ascension, than by their latitude and longitude I 
How many degrees may latitude and declination extend ? How many, terrestrial lon- 
gitude! How many, celestial longitude! What is meant by the daily acceleration of 
the stars? To how many n inutes does it amount? Illustrate this subject with an 
txaniple. 



30 



PRELIMINARY CHAPTER. 



Revolutions 


Times in which Revolutions 


Daily acceleration of the 


of the Stars. 




are 


made. 






Stare. 






days. 


h. 


min. 


Eec. 


h. 


min. 


sec. 


1 





23 


56 


4 





3 


55 


2 


1 


23 


52 


8 





7 


51 


3 


2 


23 


48 


12 





11 


47 


4 


3 


23 


44 


16 





15 


43 


5 


4 


23 


40 


20 





19 


39 


6 


5 


23 


36 


24 





23 


35 


7 


6 


23 


32 


28 





27 


31 


8 


7 


23 


28 


32 





31 


27 


9 


8 


23 


24 


36 





35 


23 


10 


9 


23 


20 


41 





39 


19 


11 


10 


23 


16 


45 





43 


14 


12 


11 


23 


12 


49 





47 


10 


13 


12 


23 


8 


53 





51 


6 


14 


13 


23 


4 


57 





55 


2 


15 


14 


23 


1 


1 





58 


58 


16 


15 


22 


57 


5 


1 


2 


54 


17 


16 


22 


53 


9 


1 


6 


50 


18 


17 


22 


49 


13 


1 


10 


46 


19 


18 


22 


45 


17 


1 


14 


42 


20 


19 


22 


41 


22 


1 


18 


38 


21 


20 


22 


37 


26 


1 


22 


33 


22 


21 


22 


33 


30 


1 


26 


29 


23 


22 


22 


29 


34 


1 


30 


25 


24 


23 


22 


25 


38 


1 


31 


21 


25 


24 


22 


21 


42 


1 


38 


17 


26 


25 


22 


17 


£ 


1 


42 


13 


27 


26 


22 


13 


1 


46 


9 


28 


27 


22 


9 


54 


1 


50 


5 


29 


28 


22 


5 


58 


1 


54 


1 


30 


29 


22 


2 


3 


1 


57 


57 


40 


39 


21 


22 


44 


2 


37 


16 


50 


49 


20 


43 


25 


3 


16 


35 


100 


99 


17 


26 


50 


6 


33 


10 


200 


199 


10 


53 


40 


13 


6 


9 


300 


299 


4 


20 


30 


19 


39 


29 


360 


359 





24 


36 


23 


35 


23 


365 


364 





4 


56 


23 


55 


3 


366 


365 





1 





23 


59 






On this account, we have not always the same constella- 
tions visible To us throughout the year. While some, that 
were not visible before, are successively rising to view in the 
east, and ascending to the meridian, others sink beneath the 
western horizon, and are seen no more, until, having passed 
through the lower hemisphere, they again reappear in the east. 

It is easy to convert right ascension into time, or time into right ascension, for 
if a heavenly body is one hour in passing over 15°, it will be one fifteenth of an 
hour, or 4 minutes, in passing over 1°. 

If the first point of Aries be on the meridian at 12 o'clock, the next hour line, 
which is 15° E. of it, will come to the meridian at 1 o'clock; the second hour 
line at 2 o'clock ; the third at 3, <fcc. Of any two bodies whose right ascensions 
are given, that one will pass the meridian_/jrsf which has the least right ascension. 

The first map of the atlas represents, upon a large scale, 
a general view of the solar system. 

This will be more fully described in the Second Part of the work. 

Do we always gee the same constellations i Explain the manner of converting right 
ascension into time, and time into right ascension. 



PRELIMINARY CHAPTER. 31 

The next six maps represent different sections of the con- 
cave surface of the heavens. The first of these exhibits the 
principal constellations visible to us in October, November 
and December ; the second, those visible in January, Febru- 
ary and March ; the third, those visible in April, May and 
June ; and the fourth, those visible in July, August and Sep- 
tember ; with the exception, however, of the constellations 
which lie beyond the 50th degree of north and south declina- 
tion, of which, indeed, those around the North Pole are al- 
ways, and those around the South Pole, never visible to us. 

These constellations are represented on the sixth and sev- 
enth maps, called circumpolar maps, which are an exact 
continuation of the others, and if joined to them at their cor- 
responding degrees of right ascension and declination, they 
might be considered as constituting one map. The scale on 
which all the above-mentioned maps are drawn is that of a 16 
inch globe. The lines drawn on the maps have been already 
defined ; and their use, being nearly the same with those in 
Geography, will be readily understood. Those which are 
drawn from right to left, on each side of the equinoctial and 
parallel to it, are called Parallels of Declination. Those 
which are drawn up and down through the maps, at intervals 
of 15°, are called Meridians of Right Ascension, or Hour 
Circles. The scale at the top and bottom of the first four 
maps, and in the circumference of the circumpolar maps, in- 
dicates the daily progress of the stars in right ascension, and 
shows on what day of the month any star will be on the me- 
ridian at 9 o'clock in the evening. 

The constellation called the Great Bear is an exception to this rule ; in this 
constellation the principal stars are marked in the order of their right ascension. 

That point of projection for the maps which would exhibit each successive 
portion of the heavens directly overhead at 9 o'clock in the evening, was chosen, 
because in summer at an earlier hour the twilight would bedim our observation 
of the etars, and at other seasons of the year it is easier to look up to stars that 
want an hour of their meridian altitude than to those which are directly over- 
head. 

It will be readily seen that the stars are so represented on the maps as to show 
their relative magnitudes. The method invented by Bayer, of designating them 
by the letters of the Greek and Roman alphabets, is adopted. Thus in each con- 
stellation the 6tars are marked alpha, beta, &c, and should the letters of the 
Greek alphabet be exhausted, those of the Roman are employed. Some of the 
stars have also proper names. 

The first four maps of the heavens are so constructed tha 

For what months does the first map represent the heavens ! For what month* does 
the second map represent the heavens ? The third ? The fourth ? What constellations 
are represented on the sixth and seventh maps .' In what manner must these six maps 
be arranged to form one complete map of the heavens? On what scale are these maps 
drawn ? What is the use of the srale at the top and bottom of the first four maps, and 
in the circumference of the circumpolar maps ? Why was that point of projection for 
the maps, which would represent each successive portion of the heavens directly over- 
head at 9 o'clock in the evening, chosen i What is the vie'thod by which t he stars are 
designated on t fie ?naps'> How mu^t the pupil, in using either of the first four map* 
imagine himstlf to jtand and to hold it? 



32 PRELIMINARY CHAPTER. 

the pupil in using them must suppose himself to face the south, 
and to hold them directly overhead in such manner that the 
top of the map shall be towards the north, and the bottom 
towards the south ; the right-hand side of the map will then 
be west, and the left-hand east. In using the circumpolar 
maps he must suppose himself to face the pole, and to hold 
them in such a manner that the day of the given month shall 
be uppermost. The Celestial Planisphere represents the 
whole heavens lying between 70 degrees of north and south 
declination, not as a surface of a concave sphere, but of a 
concave cylinder, and spread out so as to form a plain sur- 
face. A great variety of interesting problems, including 
almost all those that are peculiar to the celestial globe, may 
be solved upon it with facility and readiness. 

We may now imagine the pupil ready to begin the study 
of the visible heavens. The first thing of importance is to 
fix upon the proper starting point. This, on many accounts, 
would seem to be the North Polar Star. Its position is ap- 
parently the same every hour of the night throughout the 
year, while the other stars are continually moving. Many 
of the stars also in that region of the skies never set, so that 
when the sky is clear, they may be seen at any hour of the 
night. They revolve about the pole in small circles, and 
never disappear below the horizon. On this account they 
are said to be within the circle of perpetual apparition. On 
i,he other hand, the identity of the North Polar Star, strange 
as it may appear, is not so easily determined by those who 
are just entering upon this study, as that of some others. For 
this reason, the point directly overhead, called the zenith, 
is preferable, since upon this point every one can fix with 
certainty in whatever latitude he may be. It will be alike 
to all the central point of the visible heavens, and to it the 
pupil will learn imperceptibly to refer the bearing, motion, 
and distances of the heavenly bodies. 

That meridional point in each map, whose declination corresponds with the 
latitude of the place of observation, represents the zenith of the heavens at that 
place : and those constellations of stars which occupy this position on the maps, 
will be seen directly overhead at 9 o'clock in the evening of the day through 
which the meridian passes. — Thus in Georgia, for instanco, the starting point 
should be those stars which are situated in this meridian near the 33d degree of 
north declination, while in New England it should be those whieh are situated in 
it near the 42d degree. 



How, in using the circumpolar maps ? Describe the construction and use of the Ce- 
lestial Planisphere. "When the pupil is ready to begin the study of the visible heavens, 
what is the first step to be taken? What advantages has the North Polar Star a* a 
proper starting point? What disadvantages? What point is preferable to the Polar 
Star ? Why is it preferable ? How may the point corresponding to this be found upon 
the maps? At what time in the evening will the stars which are near this point on 
the maps, be seen directly overhead I Is it indispensably necessary to begin with the 
stars near this central meridian J 



PRELIMINARY CHAPTER. 33 

We might, however, begin with the stars near either of 
the meridians represented on the maps, the only rule of se- 
lection being to commence at that which approaches nearest 
to being overhead at the time required. 

We have chosen for our starting point in this work that 
meridian which passes through the vernal equinox at the first 
point of Aries, not only because it is the meridian from which 
the distances of all the heavenly bodies are measured ; but 
especially because the student will thus be enabled to observe 
and compare the progressive motion of the constellations ac- 
cording to the order in which they are always arranged in 
catalogues, and also to mark the constellations of the Zodiac 
passing overhead as they rise one after another in their or- 
der, and to trace among them the orbits of the Earth and 
of the other planets. 

As Greek letters so frequently occur in catalogues and maps of the stars and 
on the celestial globes, the Greek alphabet is here introduced for the use of those 
who are unacquainted with it. The capitals are seldom used for designating the 
stars, but are here given for the sake of regularity. 

THE GREEK ALPHABET. 

A « 

B 

r y 

A S 

E t 

Z i 

H n 

e e 

1 i 

K 

A A 

M (i 

N 

S | 

o 
n 

P 9 

S s 

T r 

Y 

$ <p 

X X 

a 

In 1603, John Bayer, of Augsburg, in Germany, published a complete Atlas of 
all the constellations, with the useful invention of denoting the stars in every 

What is the only rule of selection ? What is the starting point chosen for this work? 
What advantages has this meridian as a starting point? 



Alpha 


a 


Beta 


b 


Gamma 


g 


Delta 


d 


Epsilon 


e short 


Zeta 


z 


Eta 


e long 


Theta 


th 


Iota 


i 


Kappa 


k 


Lambda 


. 


Mu 


in 


Nu 


n 


Xi 


X 


Omicron 


o short 


Pi 


P 


Rho 


r 


Sigma 


s 


Tau 


t 


Upsilon 


u 


Phi 


ph 


Chi 


ch 


Psi 


ps 


Omega 


olong 



34 



PRELIMINARY CHAPTER. 



constellation by the letters of the Greek and Roman Alphabets; assigning tbe 
Greek letter a to the principal stars in each constellation, p to the second in mag- 
nitude, y to the third, and so on ; and when the Greek alphabet was exhausted, 
the notation was carried on with the Roman letters, a, b, c, &c. That the me- 
mory might not be perplexed with a multitude of names, this convenient method 
of designating the stars has been adopted by all succeeding astronomers, who 
have farther enlarged it by the Arabic notation, 1, 2, 3, &c., whenever the stars in 
the constellations outnumbered both alphabets. 



INCREASE OF SIDEREAL TIME IN MEAN SOLAR HOURS, &c. 

Increase. Incr. Incr. Incr. Incr. 



Hours. 

1 



9 
10 
11 
12 
13 
14 
15 
16 
17 
13 
19 
20 
21 
22 
23 
24 



9.857 
19.713 
29.569 
39.426 
49.282 
59.139 

1 8.995 
18.852 
28.708 
38.565 
48.421 
53.278 

2 8.134 
17.991 
27.847 
37.704 
47.560 
57.417 

3 7.273 
17.130 
26.986 
36.842 
46.699 
56.555 



Daily acceleration of 
a star in passing the 
meridian, 

m. sec. 
3 55.9095 





Incr. 




Incr. 




Incr. 




Min. 


sec. 


Min. 


sec. 


Sec. 


sec. 


Sec. 


1 


0.164 


31 


5.093 


1 


0.003 


31 


2 


329 


32 


257 


2 


006 


32 


3 


493 


33 


421 


3 


008 


33 


4 


657 


34 


585 


4 


011 


34 


5 


821 


35 


750 


5 


014 


35 


6 


936 


36 


914 


6 


016 


36 


7 


1.150 


37 


6.078 


7 


019 


37 


8 


314 


33 


242 


8 


022 


38 


9 


479 


39 


407 


9 


025 


39 


10 


643 


40 


571 


10 


027 


40 


11 


807 


41 


735 


11 


030 


41 


12 


971 


42 


900 


12 


033 


42 


13 


2.136 


43 


7.064 


13 


036 


43 


14 


300 


44 


228 


14 


038 


44 


15 


464 


45 


392 


15 


041 


45 


16 


628 


46 


557 


16 


044 


46 


17 


793 


47 


721 


17 


047 


47 


18 


957 


48 


885 


18 


049 


48 


19 


3.121 


49 


8.050 


19 


052 


49 


20 


286 


50 


214 


20 


055 


50 


21 


450 


51 


378 


21 


058 


51 


22 


614 


52 


542 


22 


060 


52 


23 


778 


53 


707 


23 


063 


53 


24 


943 


54 


871 


24 


066 


54 


25 


4.107 


55 


9.035 


25 


069 


55 


26 


271 


56 


199 


26 


071 


56 


27 


435 


57 


364 


27 


074 


57 


28 


600 


58 


528 


28 


077 


58 


29 


764 


59 


692 


29 


079 


59 


1 30 


928 


60 


857 


30 


082 


60 



090 
093 
096 
099 
101 
104 
107 

no 

112 
115 
113 
121 
123 
126 
129 
131 
134 
137 
140 
142 
145 
148 
151 
153 
156 
159 
162 
164 



GEOGRAPHY OF THE HEAYENS. 



CHAPTER I. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE MERIDIAN IN NOVEMBER. 

ANDROMEDA. 

If we look directly overhead at 10 o'clock, on the 10th of 
November, we shall see the constellation celebrated in fable 
by the name of Andromeda. It is represented on the map 
by the figure of a woman having her arms extended, and 
chained by her wrists to a rock. It is bounded N. by Cassi- 
opeia, E. by Perseus and the head of Medusa, and S. by the 
Triangles and the Northern Fish. It is situated between 20° 
and 50° of N. declination. Its mean right ascension is nearly 
15° ; or one hour E. of the equinoctial colure. 

It consists of 66 visible stars, of which three are of the 2d 
magnitude, and two of the 3d; most of the rest are small. 

The stars directly in the zenith are too small to be seen in 
the presence of the moon, but the bright star Almaack, of the 
2d magnitude, in the left foot, may be seen 13° due E., and 
Merach, of the same magnitude, in the girdle, 7° south of 
the zenith. This star is then nearly on the meridian, and 
with two others N. W. of it forms the girdle. 

The three stars forming the girdle are of the 2d, 3d, and 
4th magnitude, situated in a row, 3° and 4° apart, and are 
called Merach, Mu and Nu. 

About 2° from Nu at the north-western extremity of the 
girdle, is a remarkable nebula of very minute stars, and the 
only one. of the kind which is ever visible to the naked eye. 
It resembles two cones of ligh t, joined at their base, about 
2° in length, and i° in breadth- 



_ If we look directly overhead at 10 o'clock on the 10th of November, what constella- 
tion shall we see ? How is it represented on the map? How is it bounded? Will 
are its right ascension and declination ? How many visible stars has it ? Describe the 
girdle of Andromeda Describe the appearance 01 a remarkable nebula which lies at 
its north-western extremity. 



36 PICTURE OF THE HEAVENS. 

If a straight line, connecting Almaack with Merach, be 
produced south-westerly, 8° farther, it will reach to Delta, a 
star of the 3d magnitude in the left breast. This star may- 
be otherwise known by its forming a line, N. and S., with 
two smaller ones on either side of it; or, by its constituting, 
with two others, a very small triangle, S. of it. 

Nearly in a line with Almaack, Merach and Delta, but 
curving a little to the N. 7° farther, is a lone star of the 2d 
magnitude, in the head, called Alpheratz. This is the N. E. 
corner of the great " Square of Pegasus," to be hereafter 
described. 

It will be well to have the position of Alpheratz well fixed in the mind, because 
it is but one minute west of the great equinoctial colure. or first meridian of the 
heavens, and forms nearly a right line with Algenib in the wing of Pegasus, 14° 
S. of it, and with Beta in Cassiopeia. 30° N. of it. If a line, connecting these 
three stars, be produced, it will terminate in the pole. These three guides, in 
connection with the North Polar S:ar point out to astronomers the pos.tiun of 
that great circle in the heavens from which the right ascension of all the heav- 
enly bodies is measured. 

History.— The story of Andromeda, from which this constellation derives its 
name, is as follows : She was daughter of Cepheus. king of Ethiopia, by Cassio- 
peia. She was promised in marriage to Phineus, her uncle, when Neptune 
drowned the kingdom, and sent a sea monster to ravage the country, to appease 
the resentment which his favorite Nymphs bore against Cassiopeia, becuuse she 
had boasted herself fairer than Juno and the Nereides. The oracle of Jupiter 
Ammon was consulted, and nothing could pacify the anger of Neptune unless 
the beautiful Andromeda should be exposed to the sea monster. She was ac- 
cordingly chained to a rock for this purpose, near Joppa. (now Jaffa, in Syria.) 
and at the moment the monster was going to devour her, Perseus, who was' then 
returning through the air from the conquest of the Gorgons, saw her and was 
captivated by her beauty. 

" Chained to a rock she stood ; young Perseus stay'd 
His rapid flight, to woo the beauteous maid." 

He promised to deliver her and destroy the monster if Cepheus would give her 
to him in marriage. Cepheus consented, and Perseus instantly changed the sea 
monster into a rock, by showing him Medusa's head, which was still reeking in 
bis hand. The enraged Phineus opposed their nuptials, and a violent battle en- 
sued, in which he, also, was turned into a stone by the petrifying influence of the 
Gorgon's head. 

The morals, maxims, and historical events of the ancients, were usually com- 
municated in fable or allegory. The fable of Andromeda and the sea monster, 
might mean that she was courted by some monster of a sea-captain, who at- 
tempted to carry her away, but was prevented by another more gallant and suc- 
cessful rival. 



PISCES. 

The Fishes. — This constellation is now the first in order 
of i he 12 constellations of the Zodiac, and is usually repre- 
sented by two fishes tied a considerable distance apart, at the 
extremities of a long undulating cord, or ribbon. It occupies 

Describe the magnitude and position of Delta. How may this star be otherwise 
known? Describe the position and magnitude of Alpheratz. What position does this 
■tar occupy in the great Square of Pegasus ? Why is it important to have the position 
of this star well fixed in the mind ? What is the present order of the Fishes among the 
constellations of the Zodiac? How is it represented ? Describe iu outline and space is 
the heavens. 



pisces. 37 

a large triangular space in the heavens, and its outline at first 
is somewhat difficult to be traced. 

In consequence of the annual precession of the stars, the constellation Pisces 
has now come to occupy the sign Aries ; each constellation having advanced 
one whole sign in the order of the Zodiac. The Sun enters the sign Pisces, whiL 
the Earth enters that of Virgo, about the 19th of February, hut he does not reach 
the constellation Pisces before the 6th of March. The Fishes, therefore, are now 
called the '"Leaders of the Celestial Hosts." — (See Aries. 

That loose assemblage of small stars directly south of 
Merach, in the constellation of Andromeda, constitutes the 
Northern Fish, whose mean length is about 16°, and breadth, 
7°. Its mean right ascension is 15°, and its declination 25° 
N. Consequently, it is on the meridian the 24th of No- 
vember ; and from its breadth, is more than a w T eek in pass- 
ing over it. The Northern Fish and its ribbon, beginning at 
Merach, may by a train of small stars, be traced in a S. S. 
easterly direction, for a distance of 33°, until w T e come to the 
star El Rischa, of the 3d magnitude, which is situated in 
the node, or flexure of the ribbon. This is the principal star 
in the constellation, and is situated 2° N. of the equinoctial, 
and 53 minutes east of the meridian. 

Seven degrees S. E. of El Rischa. passing by three or four very small stars we 
come to Mira, in the Whale, a star of about the 3d magnitude, and known as the 
" Wonderful Star of 1596." El Rischa may be otherwise identified by means of 
a remarkable cluster of five stars in the form of a pentagon, about 15° E. of it. — 
See Celus. 

From El Rischa the ribbon or cord makes a sudden flex- 
ure, doubling back across the ecliptic, where we meet with 
three stars of the fourth magnitude situated in a row 3° and 
4° apart, marked on the map Zeta, Epsilon, Delta. From 
Delta the ribbon runs north and westerly along the Zodiac, 
and terminates at Beta, a star of the 4th magnitude, 11° S. 
of Markab in Pegasus. 

This part of the ribbon including the Western Fish at the 
end of it, has a mean declination of 5° N., and may be seen 
throughout the month of November, passing the meridian 
slowly to the W.. near where the sun passes it on the 1st of 
April. Twelve degrees W. of this Fish, there are 4 small 
stars situated in the form of the letter Y. The two Fishes, 
and the cord between them, make two sides of a large trian- 
gle, 30° and 40° in length, the open part of which is towards 
the N. W. When the Northern Fish is on the meridian. 

What are the size and position of the Northern Fish 7 When, and how long- is it on 
the meridian ? How may it be traced ? What is the principal star in this constellation, 
and where is it situated? How far, and in what direction from Alpha, is Mira, in the 
Whale ? By what peculiar apellation is this star known ? What is the direction of the 
ribbon from Alpha ? What stars do we meet with, where the ribbon doubles back 
across the ecliptic? What is the direction of this part of the ribbon from Delta, and 
where does it terminate ? What are its mean declination, and the time of its passing 
the meridian ? What striking clns'.er is seen about 12° W. oi'the Western Fish ? What 
geometrical figure may be conceived to be formed by the two Fishef and the cord be- 
tween them ? Where is the Western Fish when the Northern ia on the meridian ? 



38 PICTURE OF THE HEAVENS. [NOV. 

the Western is nearly 2 hours past it. This constellation is 
bounded N. by Andromeda, W. by Andromeda and Pega- 
sus, S. by the Cascade, and E. by the Whale, the Ram and 
the Triangles. 

When, to enable the pupil to find any star, its direction from another is iriven, 
the latter is always understood to be on the meridian. 

After a little experience with the maps, even though unaccompanied by di- 
rections, the inger. : us youth will be able, of himself, to devise a great many ex- 
pedients and facilities for tracing the constellations, or selecting out particular 
stars. 

History. — The ancient Greeks, who have some fable to account for the origin 
of almost every constellation, say. that as Venus and her son Cupid were one 
day on the banks of the Euphrates, they were greatly alarmed at the appearance 
of a terrible giant, named Typhon. Throwing themselves into the river, they 
were changed into fishes, and by this means escaped danger. To commemorate 
this event, Minerva placed two fishes amoni the stars. 

According to Ovid. Homer, and Virgil, this Typhon was a famous giant. He 
hid a hundred heads, like those of a serpent or dragon. Flames of devouring 
fire darted from his month and eyes. He was no sooner born, than he made war 
against heaven, and so frightened the gods, that they tied and assumed different 
shapes. Jupiter became a ram; Mercury, an ibis; Apollo, a crow; Juno, a 
cow; Bacchus, a soat ; Diana, a cat ; Venus, a fish. «fcc. The father of the gods, 
at last, put Typhon to flight, and crushed him under Mount ^;na. 

The obvioiis sentiment implied in the fable of this hideous monster, is evidently 
this : that there is in the world a description of men whose mouth is so •• full of 
cursing and bitterne-s," derision and violence, that modest virtue is sometimes 
forced to disguise itself, or flee from their presence. 

In the Hebrew Zodiac, Pisces is allotted to the escutcheon of S meon. 

No sign appears to have been considered of more malignant influence than 
Pisces. The astrological calendar describes the emblems of this constei'ai in as 
indicative of violence and death. Both the Syrians and Egyptians abstained from 
sating fish, out of dread and abhorrence ; and when tiie latter would represent 
any thing as odious, or express hatred by hieroglyphics, they painted a. fish. 



In using a circumpolar map, face the pole, and hold it up in your hands in 
such a manner that the part which contains the name of the given month shall 
be uppermost, and you will have a portraiture of the heavens as seen at that time. 

The consteF rions about the Antarctic Pole are not visible in the United States ; 
those about th Arctic or Northern Pole, are always visible. 



CASSIOPEIA. 



Cassiopeia is represented on the celestial map, in regal 
state seated on a throne or chair, holding in her left hand The 
branch of a palm tree. Her head and body are seen in the 
Milky Way. Her foot rests upon the Arctic Circle, upon 
which her chair is placed. She is surrounded by the chief 
personages of her royal family. The king, her husband, ia 
on her right hand — Perseus, her son-in-law, on her left — and 
Andromeda, her daughter, just above her. 

This constellation is situated 26° N. of Andromeda, and 
midway between it and the North Polar Star. It may be 

What are the boundaries of this cou-tellation ■> How is the ronsre!!atinn Cassiopeia 
represented on the map' By wh.m is sii • ■ i n.ui,,l. .] ? Flow i.s this con telhtion sit- 
Baled in regard to Androncia an I the i'oiar .Si .r .' 



MAP V[.] CASSIOPIlA. 39 

seen, from our latitude, at all hours of the night, and may be 
traced out at almost any season of the year. Its mean de- 
clination is 60° N. and its right ascension 12°. It is on our 
meridian the 22d of November, but does not sensibly change 
its position for several days; for it should be remembered 
that the apparent motion of the stars becomes slower and 
slower, as they approximate the poles. 

Cassiopeia is a beautiful constellation, containing 55 stars 
that are visible to the naked eye; of which four are of the 
3d magnitude, and so situated as to form, with one or two 
smaller ones, the figure of an inverted chair. 

-Wide her stars 



Dispersed, nor shine with mutual aid improved ; 
Nor dazzle, brilliant with contiguous flame : 
Their number fifty-five." 

Caph, in the garland of the chair, is almost exactly in Lhe 
equinoctial colure, 30° N. of Alpheratz. with which, and the 
Polar Star, it forms a straight line. [See note to Androme- 
da.'] Caph is therefore on the meridian the 10th of Novem- 
ber, and one hour past it on the 24th. It is the westernmost 
star of the bright cluster. Shedir*, in the breast, is the up- 
permost star of the five bright ones, and is 5° S. E. of Caph : 
the other three bright ones, forming the chair, are easily dis- 
tinguished, as they meet the eye at the first glance. 

There is an importance attached to the position of Caph 
that concerns the mariner and the surveyor. It is used, in 
connection with observations on the Polar Star, for determin- 
ing the latitude of places, and for discovering the magnetic 
variation of the needle. 

It is generally supposed that the North Polar S:ar. so called, is the real immov- 
able pole of the heavens ; but this is a mistake. It is so near the true pole that 
it has obtained the appellation of the North Polar Star;, but it is. in reality, more 
than a degree and a ha'f distant from it, and revolves about the true pole every 
24 hours, in a circle whose radius is 1° 35'. It will consequently, in 24 hours.be 
twice on the meridian, once abore, and once below (he pole; and twice at its 
greatest elongation E. and VV. [See North Polar Star.] 

The Polar Star not being exactly in the N. pole of the 
heavens, but one degree and 35 minutes on that side of it 
which is towards Caph, the position of the latter becomes 
important, as it always shows on which side of the true pole 
the polar star is. 

There is another important fact in relation to the position 

* Shedir, from El Seder, the Seder tree ; a name given to this constellation by Ulugh 
Beigh. 

When may it be seen from this latitude 1 When is it on our meridian ? How :a the 

motion of the stars affected as ihey approach the poles ? How many principal stars in 

- ellation, and what is their appearance 7 Describe the situatu 1 of Caph. 

Whin is Caph on the meridian ? What is the relative position of Shedir > Why is ttte 

position of Caph important ' 






40 PICTURE OF THE HEAVENS. [NOV. 

of this star. It is equidistant from the pole, and exactly op- 
posite another remarkable star in the square of the Great 
Bear, on the other side of the pole. [See Megrez.~\ It also 
serves to mark a spot in the starry heavens, rendered memo- 
rable as being the place of a lost star. Two hundred and 
fifty years ago, a bright star shone 5° N. N. E. of Caph. where 
now is a dark void ! 

On the 8th of November, 1572, Tycho Brahe and Corneliiu 
Gemma saw a star in the constellation of Cassiopeia, which 
became, all at once, so brilliant, that it surpassed the splendor 
of the brightest planets, and might be seen even at noonday 
Gradually, this great brilliancy diminished, until the 15th of 
March. 1573. when, without moving from its place, it became 
utterly extinct. 

Its color, during this time, exhibited all the phenomena 
of a prodigious flame — first it was of a dazzling white, then 
of a reddish 'yellow, and lastly of an ashy paleness, in which 
its light expired. It is impossible, says Airs. Somcrville, to 
imagine anything more tremendous than a conflagration that 
could be visible at such a distance. It was seen for sixteen 
months. 

Some astronomers imagined that it would reappear again 
after 150 years; but it has never been discovered since. 
This phenomenon alarmed all the astronomers of the age. 
who beheld it; and many of them wrote dissertations con- 
cerning it. 

Rev. Professor Vince, one of the most learned and pious 
astronomers of the age, has this remark:--'- The disappear- 
ance of some stars may be the destruction of that system at 
the time appointed by the Deity for the probation of its in- 
habitants; and the appearance of new stars may be the for- 
mation of new systems for new races of beings then called 
into existence to adore the works of their Creator." 

Thus, we may conceive the Deity to have been employed from all eternity, 
and thus he may continue to be employed for endless aires"; forming new systems 
of beings to adore him ; and transplanting beinits already formed into happier re- 
gions, who will continue to rise higher and higher in their enjoyments, and g& 
on to contemplate system after system through "the boundless ui;.'- 

La Place says : — As to those stars which suddenly shine forth with a very vi- 
vid light, and then immediatelydisappear.it is extremely probable ti 
conflagrations, produced by extraordinary causes, take place on their surface. 
This conjecture, continues he, is confirmed by their change of color, which is 
analogous to that presented to us on the earth by those bodies which are set on 
fire and then gradually extinguished."' 

The late eminent Dr. Good also observes that — Worlds and systems of worlds 

What memorable spot does Caph serve to mark out? Describe the phenomenon of 
the lost star. What does Mrs. Somerville s;iy of it ■ How Ion? was it seen : Has any 
thing been disci rered of it since ? How did this phenomenon affect the astronomers of 
the a?e? What does Vince Bay of the disappearance of some stars, and the new ap- 
pearance of </' hers ) Repeat the observations nf Dr. Good upon the subject of new star$ 
appearing and disappearing 



MAP VI.] CEPHEUS. 41 

are not only perpetually creating, but also perpetually disappearing. It is an ex- 
traordinary fact, that within the period of the last century, not less than thirteen 
stars, in different constellations, seem to have totally perished, and ten new ones 
to have been created. In many instances it is unquestionable, that the stars 
themselves, the supposed habitation of other kinds or orders of intelligent beings, 
together with the different planets by which it is probable they were surrounded. 
have utterly vanished, and the spots which they occupied in the heavens, have 
become blanks ! What has befallen other systems, will assuredly befall our own. 
Of the time and the manner we know nothing, but the fact is incontrovertible ; 
it is foretold by revelation; it is inscribed in the heavens; it is felt through the 
earth. Such is the awful and daily text ; what then ought to be the comment 1 
The great and good Beza, falling in with the superstition of his age, attempted 
to prove that this was a comet, or the same luminous appearance which conduct- 
ed the magi, or wise men of the East, into Palestine, at the birth of our Saviour, 
and that it now appeared to announce his second eoming ! 

About 6° N. W. of Caph, the telescope reveals to us a 
grand nebula of small stars, apparently compressed into one 
mass, or single blaze of light, with a great number of loose 
stars surrounding it. 

History. — Cassiopeia was wife of Cepheus, king of Ethiopia, and mother of 
Andromeda. She was a queen of matchless beauty, and seemed to be sensible 
of it ; for she even boasted herself fairer than Juno, the sister of Jupiter, or the 
Nereides — a name given to the sea nymphs. This so provoked the ladies of the 
sea that they complained to Neptune of the insult, who sent a frightful monster 
to ravage her coast, as a punishment for her insolence. But the anger of Nep- 
tune and the jealousy of the nymphs were not thus appeased. They demanded, 
and it was finally ordained that Cassiopeia should chain her daughter Andro- 
meda, whom she tenderly loved, to a desert rock on the beach, and leave her 
exposed to the fury of this monster. She was thus left, and the monster ap- 
proached ; but just as he was going to devour her, Perseus killed him. 

,: The savior youth the royal pair confess. 
And with heav'd hands, their daughter's bridegroom biess." 
Eusden's Ovid 



CEPHEUS. 



Cepheus is represented on the map as a king, in his royal 
robe, with a scepter in his left hand, and a crown of stars 
upon his head. He stands in a commanding posture, with 
his left foot over the pole, and his scepter extended towards 
Cassiopeia, as if for favor and defence of the nneen. 

" Cepheus illumes 
The neighboring heavens; still faifhfu. to his queen, 
With thirty-five faint luminaries mark'd." 

This constellation is about 25° N. W. of Cassiopeia, ner- 
the 2d coil of Draco, and is oil the meridian at 8 o'clock the 
3d of November; but it will linger near it for many days. 
Like Cassiopeia, it may be seen at all hours of the night, 
when the sky is clear, for to us it never sets. 

By reference to the lines on the map, which all meet in the pole, it will be evi- 
dent that a star, near the pole, moves over a much leas space in one hour, than 

There is a remarkable nebula i" this constellation; describe its situation h»A ■ 
pearunce. How is Cepheus represented; What is Ins posture 2 Where is this a • 
eteliation situated 



42 PICTURE OF THE HEAVENS. [ N0 V. 

and SSfflffSS Si£ genera,ly ' thG "*™" the P° ,e > the «*™»* A" «Pace, 

™- b vfe 

the pole, and is what the declination wants of 9o" ' °* **"" fr ° m 

In this constellation there are 35 stars visible to the naked 
eye ; of these, there glitters on the left shoulder, a star of the 
3d magnitude, called Alderamin, which with two other* of 
the same brightness, S° and 12° apart, form a slightly-curved 
line towards the N. E. The last, whose Utter name is Gam- 
ma is in the right knee, 19° N. of Caph, in Cassiopeia. The 
middle one m the line, is Alphirk, in ihe girdle. This star 
is one third of the distance from Alderamin to the pole, and 
nearly m the same right line. 

It cannot be too well understood that the bearings, or direction of one star from 
another, as g.yen in tins treatise, are strictly applicable only when the "former on£ 
ts on, or near the meridian. The bearings given, in many case. VreiM he le^ff 

gKoTwm £ Vf aPPeara 2 be their ^ relatSve JSKT?nd ta ornefif 5 ? - 
lied upon, will lead to errors. For example :— It is said, in the nrecedinir mr 

fn^ P ^ tl,at r G r ma ' in , Cepheus < beare 19 ° N - f,f Cap* in <fiS££ ThSta 

true, when Caph is on the meridian, but at this very moment wh e the anthitr 

hence, will appeal to be the same distance east of it. The reason is obvious • the 
circle which Cepheus appears to describe about the pole, is ac Wn that °if Cm 
«opeia,and cons, mently when on the east side of the poK 11 Je £ilhi£ m 
hrtmen Cassiope.a and the pole-that is, west of Cassiopeia ' Ad for the same 
SopeTa^rS^. 18011 th6WeSt £ide ° f the **?» l.«SSM5 
Let it also be remembereJ, that in speaking of the voir, which we shall have 
frequent occasion to do, in the course of this" work, the North Polar Star or S 

Snd'St?''^ '7 1 ' " " a J- way 1 m 4 :m[ : and not as sonie -vHl vaguely ap 
piehend, a point in the horizon, directly N. of us. The true pole of the heavena 

lt£ e T d J r 8t aS "K?& degrecS " 6or * our horiz ™ as we are « Xof 

!zon Lfi (^A^^VSr) N - ktitllde ' the N - P ° leWiU be42 ° ab — *» 

There are also two smaller stars about 9° E. of Alderamin 
and Alphirk, with which they form a square ; Alderamin 
being the upper, and A'phirk the lower one on the W. 8° 
apart. In the center of this square there is a brio-nt dot or 
semi-visible star. 

The head of Cepheus is in the Milky- Way, and may be 
known by three stars of the 4th magnitude in the crown, 
which form a small acute triangle, about 9° to the riHit of 
Alderamin The mean polar distance of the constellation 
is 2o°, while that of Alderamin is 28° 10'. The right ascen- 
sion of the former is 338° ; consequently, it is 22°°E. of the 
equinoctial colure. 

.iaTfromH^fi^i 1 ^"^^ 1311 - 1 tog***** tension is reckoned on the equinoc- 
tial, trom the fii*t point of Aries, E., quite round to the same point again, which 



De&be^^l?l^ a ^h e r P !'- i,1 ' :il V llst ? reinit? Scribe the hrt star in the cnrro. 

^ thf ht.Vl n?( ! ' V i \ '"'"' ""," '': r,n :l '"" u;ire ,n Ulis constellation : Where 

iff i- e ' P' Ct -l)heus. and how may it he known .• What is tl,.' mnii i „hr distance 
of this constellation j How far, and which way is it from tne « Juinrctial *£§!£** 



MAP IJ.] ARIES. 43 

h 36(P. Now 333°, measured from the same point, will reach the same point 
again, within 22° ; which is the difference between 36CP and 333°. This rule 
will apply to any other case. 

History. — This constellation immortalizes the name of the king of Ethiopia. 
The name of his queen was Cassiopeia. They were the parents of Andromeda, 
who was betrothed to Perseus. Cepheus was one of the Argonauts who accom- 
panied Jason on his perilous expedition in quest of the golden fleece. Newton 
supposes that it was owing to this circumstance that he was placed in the hea- 
vens ; and that not only this, but all the ancient constellations, relate to the Ar- 
gonautic expedition, or to persons some way connected with it. Thus, he observes 
that as Musaeus. one of the Argonauts, was the first Greek who made a ce- 
lestial sphere, he would naturally delineate on it those figures which had some 
reference to the expedition Accordingly, we have on our globes to this day, the 
Golden Ram, the ensign of the ship in which Phryxus fled to Colchis, the scene 
of the Argouautic achievements. We have also the Bull witii brazen hoofs, 
tamed by Jason ; the Twins, Castor and Pollux, two sailors, with their mother 
Leda, in the form of a Swan, and Argo, the ship itself; the watchful Dragon 
Hydra, with the Cup of Medea, and a raven upon its carcass, as an emblem of 
death ; also Chiron, the Master of Jason, with his Altar, and Sacrifice; Hercu- 
les, the Argonaut, with his club, his dart, and vulture, with the dragon, crab and 
lion which he slew ; and Orp/teus, one of the company, with his harp. All these, 
says Newton, refer 10 '.he Argonauts. 

Again ; we have Orion, the son of Neptune, or, as some say, the grandson of 
Minos, with his dogs, and hare, and river, and scorpion. We have the story of 
Perseus in the constellation of that name, as well as in Cassiopeia. Cepheus, An- 
dromeda and Cetus; that of Calisto and her son Areas, in Ursa Major; that of 
Icareus and his daughter Erigone. in Bootes and Virgo. Ursa Minor relates to 
one of the nurses of Jupiter; Auriga, to Erich;honius; Ophiuchus, to Phorbas; 
Sagittarius, to Crolus, the son of "one of the Muses ; Capricorn, to Pan, and 
Aquarius to Ganymede. We have also Ariadne's crown, Bellerophon's horse, 
Neptune : s dolphin. Ganymede's eagle, Jupiter's goat with her kids, the asses of 
Bacchus, the fishes of Venus and Cupid, with their parent, the southern fish. 
These, according to Deltoton, comprise the Grecian constellations mentione'd by 
the poet Aratus ; and all relate, as Newton supposes, remotely or immediately, 
to the Argonauts. 

It may be remarked, however, that while none of these figures refer to any 
transactions of a later date than the Argonautic expedition, yet the great disa- 
greement which appears in the mythological account of them, proves that their 
invention must have been of greater antiquity than that event, and that these con- 
stellations- were received for some time among the Greeks, befoi-e their poets re- 
ferred to them in describing the particulars of that memorable expedition. 



CHAPTER II. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE ON 
THE MERIDIAN IN DECEMBER. 

ARIES. 

The Ram. — Twenty-two centuries ago, as Hipparchus 
informs us, this constellation occupied the first sign in the 
ecliptic, commencing at the vernal equinox. But as the 
constellations gain about 50" on the equinox, at every revo- 
lution of the heavens,* they have advanced in the eclipnc 

* See " Precession of the Equinoxes," page 275. 
What was the position of Aries in the ecliptic, 22 centuries ago ' 



44 PICTURE OF HIE 17 "AVENS. [DEC. 

nearly 31° beyond it, or more than a whole sign : so that the 
Fishes now occupy the same place in the Zodiac, that Aries 
did in the time of Hipparchus ; while the constellation Aries 
.s now in the sign Taurus, Taurus in Gemini, and Gemini 
til Cancer, and so on. 

Aries is therefore now the second constellation in the 
Zodiac. It is situated next east of Pisces, and is midway 
between the Triangles and the Fly on the N. and the head 
of Cetus on the S. It contains 66 stars, of which, one is of 
the 2d, one of the 3d, and two of the 4th magnitudes. 

" First, from the east, the Ram conducts the vear ; 
Whom Ptolemy with twice nine stars adonis. 
Of which two only claim the second rank ; 
The rest, when Cynthia fills the sign, are lost." 

It is readily distinguished by means of two bright stars in 
the head, about 4° apart, the brightest being the most north- 
easterly of the two. The first, which is of the 2d magnitude, 
situated in the right horn, is called Alpha Arietis, o?simply 
Arietis ; the other, which is of the 3d magnitude, lying near 
the left horn, is called Sheratan, and may be known by an- 
other star of the 4th magnitude, in the ear, U° S. of it, called- 
Mesarthim, which is the first star in this constellation. 

Arietis and Sheratan, are one instance out of many, where 
stars of more than ordinary brightness are seen together in 
pairs, as in the Twins, the Little Dog, &c, the brightest 
star being commonly on the east. 

The position of Arietis affords important facilities to nau- 
tical science. Difficult to comprehend as it may be, to the 
unlearned, the skillful navigalbr who should be lost upon an 
unknown sea, or in the midst of the Pacific ocean, could, by 
measuring the distance between Arietis and the Moon, which 
often passes near it, determine at once not only the spot he 
was in, but his true course and distance to any known me- 
ridian or harbor on the earth. 

Lying along the moon's path, there are nine conspicuous 
stars that are used by nautical men for determining their 
longitude at sea, thence called nautical stars. 

These stars are Arietis, Aldebaran, Pollux, Reguhis, 
Spica Virginis, Antares, Altair, Fomalhaut, and Markab. 

The true places of these stars, for every clay in the year, are given in the Nau- 
tical Almanac, a valuable work published annually by the English - Board of 
Admiralty," to guide mariners in navigating the seas. They are usually pub- 
lished two or three years in advance, for the benefit of long voyages. 

That a man, says Sir John Herschel, by merely measuring the moon's appa- 
rent distance from a star, with a little portable instrument field in his hand, and 

What is its present position ? How is it now situated with respect to the surround- 
ing constellations ? What are the number and magnitude of its stars? How is this 
constellation readily ..i.stinguished? Describe the two bright stars in the head. For 
\vrtat purposes is the position ot some of the stars in Arietis important ? How many 
stars are used tor determining longitude at sea, and wheie are they situated .' By what 
general name are they called? Enumerate them 



MAP II.] ARIES. 45 

applied to his eye. even with so unstable a footing as the deck of a ship, shall say 
positively within five miles, where he is, on a boundless ocean, cannot but appear 
to persons ignorant of physical astronomy an approach to the miraculous. And 
yet. says he, the alternatives of life and death, wealth and ruin, are daily and 
hourly staked, with perfect confidence, on these marvelous computations. 

Capt. Bas.l Hall, of the royal navy, relates that he had sailed from San Bias on 
the west coast of Mexico, and after a voyage of £000 miles occupying eighty-nine 
days, arrived off Rio Janeiro, having in this interval passed through the Pacific 
ocean, rounded Cape Horn, and crossed the South Atlantic without making any 
land or seeing a single sail on the voyage. Arrived within a few days' sail of Rio, 
he took a set of lunar observations, to ascertain his true position, and the bearing 
of the harbor, and shaped his course accordingly. " I hove to," says he, ,; at 4 
in the morning, till the day should break, and then bore up ; for although it was 
hazy, we could see before us a couple of miles or so. About; 8 o'clock it be- 
came so foggy that I did not like to stand in larther, and was just bringing the 
ship to the wind again before sending the people to breakfast when it suddenly 
cleared off, and I had the satisfaction of seeing the great Sugar-loaf rock, which 
stands on one side of the harbor's mouth, so nearly right ahead that we had not 
to alter our course above a point in order to hit the entrance of Rio. This was 
the first land we had seen for three mouths, after crossing so many seas, and 
being set backwards and forwards by innumerable currentsand foul winds." 

Arietis comes to the meridian about 12 minutes after 
Sheratan, on the 5th December, near where the sun does in 
midsummer. Arietis, also, is nearly on the same meridian 
with Almaack, in the foot of Andromeda. 19° N. of it, and 
culminates only four minutes after it. The other stars in this 
constellation are quite small, constituting that loose cluster 
which we see between the Fly on the north, and the head 
of Cetus on the south. 

When Arietis is on the meridian, Andromeda and Cas- 
siopeia are a little past the meridian, nearly overhead, and 
Perseus with the head of Medusa, is as far to the east of it. 
Taurus and Auriga are two or three hours lower down; 
Orion appears in the S. E., and the Whale on the meridian, 
just below Aries, while Pegasus and the Swan are seen 
half-way over in the west. 

The manner in which the ancients divided the Zodiac into 12 equal parts, was 
both simple and ingenious. Having no instrument that would measure time ex- 
actly, " they took a vessel, with a small hole in the bottom, and having filled it 
with water, suffered the same to distill, drop by drop, into another vessel set be- 
neath to receive it, beginning at. the moment when some star rose, and continuing 
till it rose the next following night, when it would have performed one complete 
revolution in the heavens. The water falling down into the receiver they divi- 
ded into 12 equal parts ; and having twelve other small vessels in readiness, each 
of them capable of containing one part, they again poured all the water into the 
upper vessel, and observing the rising of some star in the Zodiac, at the same time 
suffered the water to drop into one of the small vessels. And as soon as it was 
full, they removed it, and set an empty one in its place. Just as each vessel was 
full, they took notice what star of the Zodiac rose at that time, and thus continued 
the process through the year, until the 12 vessels were filled." 

Thus the Zodiac was "divided into 12 equal portions, corresponding to the 12 
months of the year, commencing at the vernal equinox. Each of these portious 
served as the visible representative or sign of the month it appeared in. 

When does Arietis pass the meridian? What other brilliant star is on the meridian 
nearly at the same time ? When Aries is on the meridian, what other constellations 
are immediately in view ? Describe the manner in which the ancients divided tlie 
Zodiac. At ichat point of the Zodiac did this division commence I 



46 PICTURE OF, THE HEAVENS. [DEC. 

All those stars in the Zodiac which were observed to rise while the first vessel 
was rilling, were consiellated and included in the first sign, and called Aries, ac 
animal held in great esteem by the shepherds of Chaldea. All those stars in the 
Zodiac which rose while the second vessel was filling, were consiellated and in- 
cluded in ihe second sign, which, for a similar reason, was denominated Taurus • 
and all tnose stars which were observed to rise while the third ve.-sel was rilling, 
were constellated in the third sign, and called Gemini, in allusion to the twin 
season of the flocks. 

Thus each sign of 30° in the Zodiac, received a distinctive appellation, accord- 
ing to the fancy or superstition of the inventors; which names have ever since 
been retained, although the constellations themselves have since left their nom- 
inal signs more than 30° behind. The sign Aries, therefore, included all the stars 
embraced in the first 30° of the Zodiac, and no more. The sign Taurus, in like 
manner, included all those stars embraced in the next 3CP of the Zodiac, or those 
between 30° and 60°. and so of the rest. Of those who imagine that the twelve 
constellations of the Zodiac refer to the twelve tribes of Israel, some ascribe Aries 
to the tribe of Simeon, and others, to Gad. 

History. — According to fable, this is theram which bore the golden fleece, 
and carried Phryxus and his sister Helle through the air, when they fled to Col- 
chis from the persecution of their stepmother Ino. The rapid motion of the ram 
in bis aerial flight high above the earth, caused the head of Helle to turn with 
giddiness, and she fell from his back into that part of the sea which was after- 
wards called Hellespont, in commemoration of the dreadful event. Phryxus ar- 
rived safe at Colchis, but was soon murdered by his own father-in-law, JEtes, 
who envied him his golden treasure. This gave rise to the celebrated Argouau- 
tic expedition under the command of Jason, for the recovery of the golden fleece. 

Nephele, queen of Thebes, having provided her children, Phryxus and Helle, 
with this noble animal, upon which they might elude the wicked designs of those 
who sought their life, was afterwards changed into a cloud, as a reward for her 

Earental solicitude; and the Greeks ever after called the clouds by her name, 
ut the most probable account of the origin of this constellation is given in a 
preceding paragraph, where it is referred to the flocks of the Chaldean shepherds. 

During the campaigns of the French army in Egypt, General Dessaix discov- 
ered among the ruins at Dendera, near the banks of the Nile, the great temple 
supposed by some to have been dedicated to Isis, the female deity of the Egyp- 
tians, who believed that the rising of the Nile was occasioned by the tears which 
she continually shed for the loss of her brother Osiris, who was murdered hy 
Typhon. 

Others suppose this edifice was ereeted for astronomical purposes, from the 
circumstance that two Zodiacs were discovered, drawn upon the ceiling, on 
opposite sides. On both these Zodiacs the equinoctial points are in Leo, and not 
in Aries ; from which it has been concluded, by those who pertinaciously endea- 
vor to array the arguments of science against the chronology of the Bible and 
the validity of the Mosaic account, that these Zodiacs were constructed when the 
sun entered the sign Leo, which must have been 9720 years ago, or 4000 years 
before the inspired account of the creation. The infidel writers in France and 
Germany maKe it 10,000 years before. But we may "set to our seal." thai 
whatever is true in fact and correct in inference on this subject will be found, iu 
the end, not only consistent with the Mosaic record, but with the common mean- 
ing of the expressions it uses. 

The discovery of Champolhon has put this question for ever at rest; and M. 
Latronne, a most learned antiquary, has very satisfactorily demonstrated that 
these Egyptian Zodiacs are merely the horoscopes of distinguished personages, 
or the precise situation of the heavenly bodies in the Zodiacal their nativity. 
The idea that such was their purpose and origin, first suggested itsell to this 
gentleman on finding, in the box of a mummy, a similar Zodiac, with such in- 
scriptions and characters as determined it to be the horoscope of the deceased 
person. 

Of all the discoveries of the antiquary among the relics of ancient Greece, the 

What did each of these portions of the Zodiac serve ^ What star* icere placed in the 
first sign ? Wrtat name icas given to the constellation thus formed ? Wha ! 
placed in the second tignf What was the second constellation calletll Wliat start 
were placed in the third sign, and ichat was it called 1 Are Vie same nan u 
lainedf What dee* this precession, or going forward oftixt ttart amount to in a year I 



MAP II. J CETUS. 47 

ruins of Palmyra, the gigantic pyramids of Egypt, the temples of their gods, 01 
the sepulchres of their kings, scarcely one so aroused and riveted the curiosity of 
the learned, as did the discovery of Champollion the younger, which deciphers 
the hieroglyphics of ancient Egypt. 

The potency of this invaluable discovery has already been signally manifested 
in settling a formidable controversy between the champions of infidelity and 
those who maintain the Bible account of the creation. It has been shown that 
the constellation Pisces, since, the days of Hipparchus, has come, by reason of 
the annual precession, to occupy the same apparent place in the heavens that 
Aries did two thousand years ago. The Christian astronomer and the infidel 
are perfectly agreed as to the fact, and the amount of this yearly gain in the ap- 
parent motion of the stars. They both believe, and both can demonstrate, that 
the fixed stars have gone forward in the Zodiac about 50" of a degree in every 
revolution of the heavens since the creation ; so that were the world to light upon 
any authentic inscription or record of past ages, which should give the true po- 
sition or longitude of any particular star at that time, it would be easy to fix an 
unquestionable date to such a record. Accordingly, when the famous '• Egyp- 
tian Zodiacs," which were sculptured on the walls of the temple at Dende'ra, 
were brought away en masse, and exhibited in the Louvre at Paris, they enkin- 
dled a more exciting interest in the thousands who saw them, than ever did the 
entrance of Napoleon. "Educated men of every order, and those who had the 
vanity to think themselves such." says the commentator of Champollion, " rush- 
ed to behold the Zodiacs. These Zodiacs were immediately published and 
commented upon, with more or less good faith and decorum. 'Science struck 
out into systems very bold ; and the spirit of infidelity, seizing upon the discov- 
ery, flattered itself with the hope of drawing from thence new support. It wps 
utijusiifiably taken for granted, that the ruins of Egypt furnished astronomy wiih 
monuments, containing observations that exhibited the state of the heavens in 
the most remote periods. Starting with this assumption, a pretence was made ^i 
demonstrating, by means of calculations received as infallible, that the celestial 
appearances assigned to these monuments extended back from forty-five to sixty- 
five centuries; that the Zodiacal system to which they must belong, dated back 
fifteen thousand years, and must reach far beyond the limits assigned by Moses 
to the existence of the world." Among those who stood forth more or less bold 
as the adversaries of Revelation, the most prominent was M. Dupuis, the famous 
author of U origine de tons les Citltes. 

The infidelity of Dupuis was spread about by means of pamphlets, and the ad- 
vocates of the Mosaic account were scandalized " until anew Alexander arose to 
cut the Gordian knot, which men had vainly sought to untie. This was Cham- 
pollion the younger, armed with his discovery." The hieroglyphics now speaK 
a language tttat all can understand, and no one gainsay. " The Egyptian Zodiacs, 
then," says Latronne, '"relate in no respect to astronomy, but to" the idle phan- 
tasies of judicial astrology, as connected with the destinies of the emperors who 
made or completed them." 



CETUS. 

The Whale. — As the whale is the chief monster of the 
deep, and the largest of the aquatic race, so is it the largest 
conslellation in the heavens. It occupies a space of 50° in 
length, E. and W., with a mean breadth of 20° from N. to S. 
It is situated below Aries and the Triangles, with a mean 
declination of 12° S. It is represented as making its way 
to the E., with its body below, and its head elevated above 
the equinoctial : and is six weeks in passing the meridian. 

What :-. the en ni'svativc size of the. Whale ? What is its extent ? Where is it situ 
tfed '.: ' • l.i-i: •' ■ V.'haV in rassins the meridian? 



48 PICTURE OF THE HEAVENS. [DEC. 

Its tail comes to the meridian on the 10th of November, and 
its head leaves it on the 22d of December. 

This constellation contains 97 stars ; two of the 2d mag- 
nitude, ten of the 3d, and nine of the 4th. The head of Cetus 
may be readily distinguished, about 20° S. E. of Aries, by 
means of five remarkable stars, 4° and 5° apart, and so situ- 
ated as to form a regular pentagon. The brightest of these 
is Menkar, of the 2d magnitude, in the nose of the Whale. 
It occupies the S. E. angle of the figure. It is 3J° N. of the 
equinoctial, and 15° E. of El Rischain the bight of the cord 
between the Two Fishes. It is directly 37° S. of Algol, 
and nearly in the same direction from the Fly. It makes 
an equilateral triangle with Arietis and the Pleiades, being 
distant from each about 23° S., and may otherwise be 
known by a star of the 3d magnitude in the mouth, 3° W. 
of it, called Gamma, placed in the south middle angle of the 
pentagon. 

Nu is a star of the 4th magnitude, 4° N. W. of Gamma, 
and these two constitute the S. W. side of the pentagon in 
the head of the Whale, and the N. E. side of a similar ob- 
long figure in the neck. 

Three degrees S. S. W. of Gamma, is another star of the 
3d magnitude in the lower jaw, marked Delta, constituting 
the E. side of the oblong pentagon ; and 6° S. W. of this, is 
a noted star in the neck of the Whale, calied Mira, or the 
" wonderful star of 1596," which forms the S. E. side. This 
variable star was first noticed as such by Fabricius. on the 
13th of August, 1596. It changes from a star of the 2d mag- 
nitude so as to become invisible once in 234 days, or about 
7 times in 6 years. Herschel makes its period 331 days, 10 
hours, and 19 minutes ; while Hevelius assures us that it once 
disappeared for 4 years; so that its true period, perhaps, has 
not been satisfactorily determined. 

The whole number of stars ascertained to be variable amounts to only 15 ; 
while those which are suspected to be variable, amount to 37. 

Mira is 7° S. S. E. of El Rischa, in the bend or knot of 
the ribbon which connects the Two Fishes. Ten degrees 
S. of Mira. are 4 small stars, in the breast and paws, about 
3° apart, which form a square, the brightest being on the E. 

When does it approach, and when does it leave the meridian ? What is the whole 
number ot stars in Cetus? What is the magnitude of the principal ones ? How may 
the head of Cetus be distinguished ? What are the name and position of the brightest? 
How far is it from the equinoctial, and the principal star in the Fishes ! What is its di- 
rection from Algol and the Fly .' With what stars does it form an equilateral triangle ? 
How may it otherwise be known? Describe the position of ISu. Describe the situation 
of Delta and .Mira. When and by whom was this star discovered to be variable ? 
What :ire the extent and period of tins variation ? How long docs Herschel make it? 
What rloes Hevelius say of it? Has the true period of Mira been satisfactorily deter- 
mined ) How fur. and which way is Mini from Alpha, in the knot of the ribbon ? What 
tour smail stars do you observe to" 8. of Mira 1 



MAP II. J PERSEUS, ET CAPUT MEDUSA. 49 

Ten degrees S. W. of Mira. is a star of the 3d magnitude 
in the heart, called Baten Kaitos, which makes a scalene 
triangle with two other stars of the same magnitude 7° and 
10° W. of it : also, an equilateral triangle with Mira and 
the easternmost one in the square. 

A great number of geometrical figures may be formed from the stars in this, 
and in most of the other constellations, merely by reference to the maps : but it 
is better that the student should exercise his own ingenuity in this way with re- 
ference to the stars themselves, for when once he has constructed a group into 
any letter or figure of his own invention, he never will forget it. 

The teacher should therefore require his class to commit to writing the result 
of their own observations upon the relative position, magnitude aud figures of 
the princioal stars in each constellation. One evening's exercise in this way will 
disclose to the student a surprising multitude of crosses, squares, triangles, arcs 
and letters, by which he will be better able to identify and remember them, than 
by any instructions that could be given. 

"For example : Mira and Baten in the Whale, about 10° apart, make up the S. 
E. or shorter side of an irregular square, with El Rischa in the node of the rib- 
bon, and another star in the Whale as far to the right of Baten. as El Rischa is 
above Mira. Again, 

There are three stars of equal magnitude, forming a straight line W. of Baten ; 
from which, to the middle star is 1QP, thence to the W. one \2h ; and S p or 9° S. 
of this line, in a triangular direction, is a bright star of the second magnitude in 
the coil of the tail, called Diphda. 

In a southerly direction, 25° below Diphda. is Alpha in the head of the Phe- 
nix, and about the same distance S. W. is Fomalhaur, in the mouth of the South- 
ern Fish, formins together a large triangle, with Diphda in the vertex or top 
of it. 

That fine cluster of small stars S. of tne little square in the Whale, constitutes 
a part of a new constellation called the Chymical Furnace. The two stars N. E. 
and the three to the southward of the little square, are in the river Eridanus. 

History. — This constellation is of very early antiquity ; though most writers 
consider it the famous sea-monster sent by Neptune to' devour Andromeda be- 
cause her mother Cassiopeia had boasted herself fairer than Juno or the Sea 
Nymphs ; but slain by Perseus and placed among the stars in honor of his achieve- 
ment. 

" The winged hero now descends, now soars, 
And at his pleasure the vast monster gores. 
Deep in his back, swift stooping from above, 
His crooked sabre to the hilt he drove.'' 

It is quite certain, however, that this constellation had a place in the heavens 
long prior to the time of Perseus. When the equinoctial sun in Aries, which is 
right over the headof Cetus, opened the year, it was denominated the Preserver, 
or Deliverer, by the idolaters of the East. On this account, according to Pausa- 
nias, the sun was worshiped, at Eieusis, under the name of the Preserver or 
Savior. 

'■ With gills pulmonic breathes the enormous whale, 
And spouts aquatic columns to the gale ; 
Sports on the shining wave at noontide hours, 
And shifting rainbows crest the rising showers." — Daricin. 



PERSEUS, ET CAPUT MEDUSA. 

Perseus is represented with a sword in his right hand, the 
nead of Medusa in his left, and wings at his feet. It is situa- 

How is Baten Kaito3 situated ? What is said of the various figures that different 
eonttellations exhibit) Give an example. Of what constellation da 

$ r stars of the little sjuare in the Whale, constitute a -parti How is the constellation 
emeus represented? 



50 



PICTURE OF THE HEAVENS. 



[DEC. 



ted directly N. of the Pleiades and the Fly, between Andro- 
meda on the W. and Auriga on the E. Its mean declination 
is 46° N. It is on the meridian the 24th of December. It 
contains, including the head of Medusa, 59 stars, two of which 
are of the 2d magnitude, and four of the 3d. According to 
Eudosia, it contains, including the head of Medusa, 67 stars. 

' Perseus next, 



Brandishes high in heaven his sword of flame, 
And holds triumphant the dire Gorgon's head, 
Flashing with fiery snakes ! the stars he counts 
Ave sixty-sex en ; and two of these he boasts, 
Nohly refulgent in the second rank — 
One in his vest, one in Medusa's head." 

The Head of Medusa is not a separate constellation, but 
forms a part of Perseus. 

It is represented as the trunkless head of a frightful Gor- 
gon, crowned with coiling snakes, instead of hair, which the 
vietorJPerseus holds in his hand. 

There are, in all, about a dozen stars in the Head of Me- 
dusa; three of the 4th magnitude, and one, varying alter- 
nately from the 2d to the 4ih magnitude. This remarkable 
star is called Algol. It is situated 12° E. of Almaack, in the 
foot of Andromeda, and may be known by means of three 
stars of the 4th magnitude, lying a few degrees S. W. of it, 
and forming a small triangle. 

It is on the meridian the 21st of December; but as it con- 
tinues above the horizon 18 hours out of 24. it may be seen 
every evening from September to May. It varies from the 
2d to the 4th magnitude in about 31 hours, and bade again 
in the same time; after which it remains steadily brilliant for 
2f days, when the same changes recur. 

The periodical variation of Algol was determined in 1783, 
by John Goodricke of York, (Eng.,) to be 2 days. 20 hours, 
48 minutes, and 56 seconds. 

Dr. Herschel attributes the variable appearance of Algol 
to spots upon its surface, an 1 thinks it has a motion on its 
axis similar to that of the sun. He also observes, of variable 
stars generally: — ' ; The rotary motion of stars upon their 
axis is a capital feature in their resemblance to the sun. It 
appears to me now. that we cannot refuse to admit such a 
motion, and that indeed it may be as evidently proved 



Where is it situated? What is its declination, and when i* it on the meridian 1 
tt'hut is the whole number of its stars ? Whit is the magnitude of il 
Of what constellation dot s Caput Medusa! form a part How is i: repre.-ented ' 
is the whole number ofits r>:-r< ■ W'l, ' i- die maim tmleof the prim- t. 

are the name and position of the variable star in tlii< constel - t on the 

meridian, and how long may it he .seen J In what time does it vary from the 2d to the 
How Ion? is it steadily brilliant' When and by 
•I- What is its exact period ? To whal 



MAP III.] PERSEUS ET CAPUT MEDUS-E. 51 

diurnal motion of the earth. Dark spots, or large portions 
of the surface less luminous than the rest, turned alternately 
in certain directions either toward, or from us, will account 
for all the phenomena of periodical changes in the luster of 
the stars, so satisfactorily, that we certainly need not look 
out for any other cause." 

It is said, that the famous astronomer Lalande, who died at Paris in 1807. was 
wont to remain whole nights, in his old age. upon the Pont Xeuf, to exhibit to 
the curious the variations in the brilliancy of the star Algol. 

Nine degrees E. by N. from Algol, is the bright star Al- 
genib, of the 2d magnitude, in the side of Perseus, which 
with Almaack, makes a perfect right angle at Algol, with the 
open part towards Cassiopeia. By means of this strikingly 
perfect figure, the three stars last mentioned may always be 
recognized without the possibility of mistaking them. Al- 
g-enib may otherwise be readily distinguished by its being 
the brightest and middle one of a number of stars lying four 
and five degrees apart, in a large semicircular form, curving 
towards Ursa Major. 

Algenib comes to the meridian on the 21st December, 15 
minutes after Algol, at which time the latter is almost directly 
overhead. When ihese two stars are on the meridian, that 
beautiful cluster, the Pleiades, is about half an hour E. of 
it : and in short, the most brilliant portion of the starry hea- 
vens is then visible in the eastern hemisphere. The glories 
of the scene are unspeakably magnificent ; and the student 
who fixes his eye upon those lofty mansions of being, can- 
not faii to covet a knowledge of their order and relations, 
and to c: reverence Him who made the Seven Stars and 
Orion." 

The Milky Way around Perseus is very vivid, being un- 
doubtedly a rich stratum of fixed stars, presenting the most 
wonderful and sublime phenomenon of the Creator's power 
and greatness. Kohler, the astronomer, observed a beautiful 
nebula near the face of Perseus, besides eight other nebulous 
clusters in different parts of the constellation. 

The head and sword of Perseus are exhibited on the circumpolar map. That 
very bright star 23° E. of Algol, is Capella in the Charioteer. 

History. — Perseus was the son of Jupiter and Danae. He was no sooner born 
than he was cast into the sea with his mother; but being driven on the coasts 
of one of the islands of the Cyclades, they were rescued by a fisherman, and 
carried to Polydectes, the kin^ of the place, who treated them wiih ureat hu- 
manity, and intrusted them to the care of the priests of Minerva's temple. His 
rising genius and manly courage soon made him a favorite of the gods. At w 

How may Algenib be distinguished ! When is it on the meridian? H.iw lm? arter 
Algol? "When these two stars are on the meridian, what beautiful cluster s half an 
hour east of it ? What is the general appearance of the eastern hemisi here at that 
time ! What is the Appearance of the Milky Way around Perseus ? What 'ichulu; have 
been observed in this constellation 1 



52 PICTURE OF THE HEAVEN 8. [JAN. 

great feast of Polydectes, all the nobles were expected lo present the kin:; with 
a superb and beautiful horse ; but Perseus, who owed his benefactor m 
wishing to be thought less munificent than the rest, engaged to bring him the 
head of Medusa, the only one of the three Gorgons who was subject to mortality. 
The names of the other two were Stheno and Euryale. They were rep: 
with serpents wreathing round their heads instead of hair, having yellow \vin13 
and brazen hands; their bodies which grew indissolubly together were c 
with impenetrable scales, and their very looks had the power of turning into 
stones all those on whom they fixed their eya^ 

To equip Perseus for this perilous enterprffl^Tuto, the god of the infernal 
regions, lent him his helmet, which had the power of rendering the wearer in- 
visible. Minerva the goddess of wisdom, furnished him with her buckler, which 
was as resplendent as a polished mirror ; and he received from Mercury wisps 
for his feet, and a dagger made of diamonds. Thus equipped, he mounted into 
the air, conducted by Minerva, and came upon the monsters who. with the 
watchful snakes about their heads, were all asleep. He approached them, and 
with a courage which amazed and delighted Minerva, cut off with one blow Me- 
dusa's head. The noise awoke the two immortal sisters, but Pluto's helmet ren- 
dered Perseus invisible, and the vengeful pursuit of the Gorgons proved fruitless. 
" In the mirror of his polished shield 
Reflected, saw Medusa slumbers take, 
And not one serpent by good chance awake ; 
Then backward an unerring blow he pped, 
And from her body lopped at once her head." 
Perseus then made his way through the air, with Medusa's head yet reeking 
in his hand, and from the blood which dropped from it as he flew, sprang all 
those innumerable serpents that have ever since infested the sandy deserts of 
Libya. 

" The victor Perseus, with the Gorgon head, 
O'er Libyan sands his airy journey sped, 
The gory drops distilled, as swift he flew. 
And from each drop envenomed serpents grew." 
The destruction of Medusa rendered the name of Perseus immortal, and he 
was changed into a constellation at his death, and placed among the stars, with 
the head of Medusa by his side. 






CHAPTER III. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE MERIDIAN IN JANUARY. 

The constellations which pass our meridian in the months of January, Febru- 
ary and March, present to us the most brilliant and interesting portion of the 
heavens ; embracing an annual number of stars of the highest order and bright- 
ness, a'l so conspicuously situated, that the most inexperienced can easily trace 
them out. 

TAURUS. 

The Bull is represented in an attitude of rage, as if about 
to plunge at Orion, who seems to invite the onset by provoca- 
tions of assaul t and defiance. Only the head and shoulders of 
the animal are to be seen; but these are so distinctly marked 

What is the comparative brilliancy cf the constellations which pass the meridian in 
January, February and March) How in Taurus represented ? What parts of the an- 
imal are to be seen 1 



MAP III. J TAURUS. 53 

that they cannot be mistaken. Taurus is now the second 
sign and third constellation of the Zodiac; but anterior to 
the time of Abraham, or more than 4000 years ago, the ver- 
nal equinox took place, and the year opened when the sun 
was in Taurus ; and the Bull, for the space of 2000 years, 
was the prince and leader of the celestial host. The Ram 
succeeded next, and now the Fishes lead the year. The head 
of Taurus sets with the sun about the last of May, when the 
opposite constellation, the Scorpion, is seen to rise in the S. 
E. It is situated between Perseus and Auriga on the north. 
Gemini on the east, Orion and Eridanus on the south, and 
Aries on the west, having a mean declination of 16° N. 

It contains 141 visible stars, including two remarkable 
clusters called the Pleiades and Hyades. The first is now 
on the shoulder, and the latter in the face of the Bull. 

The Pleiades, according to fable, were the seven daughters 
of x^tias and the nymph Pleione,* who were turned into stars, 
«vith their sisters the Hyades, on account of their amiable 
virtues and mutual affection. 

Thus we every where find that the ancients, with all their barbarism and 
idolatry, entertained the belief that unblemished virtue and a meritorious life 
would meet their reward in the sky. Thus Virgil represents Magnus Apollo as 
bending from the sky to address the youth lulus : — 

4; Macte nova virtute puer ; sic itur ad astra ; 
Diis genite, et geniture Deos." 

" Go on, spotless boy, in the paths of virtue ; it is the way to the stars ; offspring 
of the gods thyself— so shall thou become the father of gods." 

Our disgust at their superstitions may be in some measure mitigated, by seri- 
ously reflecting, that had some of these personages lived in our day, they had 
been ornaments in the Christian church, and models of social virtue. 

The names of the Pleiades are Alcione, Merone, Maia, 
Electm, Tayeta, Sterope and Celeno. Merope was the only 
one who married a mortal, and on that account her star is 
dim among her sisters. 

Although but six of these are visible to the naked eye, yet 
Dr. Hook informs us that, with a twelve feet telescope, he 
saw 78 stars ; and Rheita affirms that he counted. 200 stars 
in this small cluster. 

The most ancient authors, such as Homer, Attalus, and Geminus. counted only 
six Pleiades; but Simonides, Varro, Pliny, Aratus, Hipparchus, and Ptolemy, 
reckon them seven in number ; and it was asserted, that the seventh had been 
seen before the burning of Troy ; but this difference might arise from the differ- 
ence in distinguishing them with the naked eye. 



What is the numerical order of Taurus among the sifrns and constellations of the 
Zodiac J What was its position in the Zodiac before the time of Abraham ? How long 
did it continue to lead the celestial host? What constellation succeeded next ? Where 
is Taurus now situated > How m.iny stars does it contain ? What remarkable clusters 
are in this constellation ? Where are these placed ? Mention the name* of the Plei 
ailes. Which of these seven stars is not seen, and why? Are these six all that can U# 
seen through the telescope ? 



54 PICTURE OF THE HEAVENS. [JAN. 

The Pleiades are so called from the Greek word, k\cciv 
pleein, to sail; because, at this season of the year, they 
were considered "the star of the ocean" to the benio-hted 
mariner.* Alcyone, of the 3d magnitude, being the bright- 
est star in this cluster, is sometimes called the light of the 
Pleiades. The other five are principally of the 4th and 5th 
magnitudes. 

The Pleiades, or, as they are more familiarly termed, the 
seven stars, come to the meridian 10 minutes before 9 
o'clock, on the evening of the 1st of January, and may serve, 
in place of the sun, to indicate the time, and as a guide (o 
the surrounding stars. 

According to Hesiod, who wrote about 900 years before the birth of our Sa- 
viour, the heliacal rising of the Pleiades took place on the 11th of May. about the 
time of harvest. 

"When, Atlas-born, the Pleiad stars arise 
Before the sun above the. dawning skies, 
'Tis time to reap ; and when they sink below 
The morn-illumin'd west, 'tis time to sow." 
Thus, in all ages, have the stars been observed by the husbandman, for ,; signs 
and for seasons." 

Pliny says that Thales. the Miletan astronomer, determined the cosmical setting 
of the Pleiades to be 25 days after the autumnal equinox. This would make a 
difference between the setting at that time and the present, of 35 days, and as a 
day answers to about 59' of the ecliptic, these days will make 34° 25'. This di- 
vided by the annual precession (50|-"). will give 2405 years since the time of 
Thales. Thus does astronomy become the parent of chronology. 

If it be borne in mind that the stars uniformly rise, come to the meridian, and 
set about four minutes earlier every succeeding night.it will be very easy to 
determine at what time the seven stars pass the meridian on any night subse- 
quent or antecedent to the 1st of January. For example : at what time will the 

* Virgil, who flourished 1200 years before the invention of the magnetic needle, says 
that the stars were relied upon, in the first ages of nautical enterprise, to guide the 
rude bark o ( ver the seas. 

" Tunc alnos primum fluvii sensere cavatas ; 
Navita turn stellis numeros, et nomina fecit, 
Pleiadas, Hyadas, claramque Lycaonis Arcton." 
" Then first on seas the shallow alder swam ; 
Then sailors quarter'd heaven, and found a name 
For every fix'd and every wand'ring star— 
The Pleiade.3, Hyades, and the Northern Car." 

The same poet also describes Palinurus, the renowned pilot of the Trojan fleet, as 
watching the face of the nocturnal heavens. 

" Sidera cuncta notat tacito labentia ccelo, 
Arcturum, pluviasque Hyadas, geminosque Triones, 
Armatumque auro circumspicit Oriona." 
" Observe the stars, and notes their sliding course, 
The Pleiades, Hyades, and their wat'ry force ; 
And both the Bears is careful to behold, 
And bright Orion, arm'd with burnish'd gold." 
cious pilot was once so intent in gazing upo 
overboard, and was lost to his companions. 
" Headlong he fell, and struggling in the main. 
Cried out for helping hands, but cried in vain." 

From what circumstance do the Pleiades derive their name ? What is the brightest 
»f the Pleiades called? What is the size of the rest? When are the Pleiades on the 
aneridian ? How much earlUr do the stars i he, come to the meridian, and set, every 
succeeding night ? 



MAP III. J TAURUS. 55 

seven stars culminate on the 5th of January 7 Multiply the 5 days by 4 and take 
the result from the time they culminate on the 1st, and it will give 30 minutes 
after 8 o'clock in the evening. 

The Pleiades are also sometimes called Vergilicz, or the 
« Virgins of spring ;" because the sun enters this cluster in 
the "season of blossoms." about the 18th of May. He who 
made them alludes to this circumstance when he demands 
of Job: "Canst thou bind the sweet influences of the Plei- 
ades," &c— [Job 38 : 31.] 

The Syrian name of the Pleiades is Succoth, or Succoth- Benoth, derived from 
a Chaldaic word, which signifies " to speculate, to observe," and the ;i Men of 
Succoth" (2 Kings 17 : 30) have been thence considered observers of the 
stars. 

The Hyades are situated 11° S. E. of the Pleiades, in the 
face of the Bull, and may be readily distinguished by means 
of five stars* so placed as to form the letter V. The most 
brilliant star is on the left, in the top of the letter, and called 
Aldebaran ; from which the moon's distance is computed. 

" A star of the first magnitude illumes 
His radiant head ; and of the second rank. 
Another beams not far remote." 

Aldebaran is of Arabic origin, and takes iis name from 
two words which signily. K He went before, or led the way " — 
alluding to that period in the history of astronomy when this 
star led up the starry host from the vernal equinox. It comes 
to the meridian at 9 o'clock on the 10 of January, or 48£ 
minutes after Alycone, on the 1st. When Aries is about 27° 
high, Aldebaran is just rising to the east. So Manilius; — 

" Thus when the Ram hath doubled ten degrees, 
And join'd seven more, then rise the Hyades." 

A line 15j° E. N. E. of Aldebaran will point out a bright 
star of the 2d magnitude in the extremity of the northern 
horn, marked Beta or El Nath; (this star is also in the foot 
of Auriga, and is common to both constellations.) From 
Beta in the northern horn, to Zeta, in the tip of the southern 
horn, it is 8°, in a southerly direction. This star forms a 
right angle with Aldebaran and Beta. Beta and Zeta, then, 
in the button of the horns, are in a line nearly north and 
south, 8° apart, with the brightest on the north. That very 
bright star 17*° N. of Beta, is Capella, in the constellation 
Auriga. 

* The ancient Greeks counted seven in this cluster :— 

" The Bull's head shines with seven refulgent flames, 
Which, Grecia, Hyades, fiom their showering, names." 

At what time will the seven stars culminate on the 5th January ? By what other 
names are they sometimes called, and why » What allusion is made to this cluster in 
the ancient Scriptures ? Describe the situation and appearance of the Hyades. What 
is the brightest of them called? What is the origin of the word Aldebaran. and to 
what does it allude? When does Aldebaran culminate ? Describe the po.-ition of Beta. 
"What are the name and direction of the star in the southern horn' Wiiat is the rela- 
tive position of these stars ? What very bright star is seen 17° 30' i\. of I3eta ? 



56 PICTlllE OF THE HEAVENS. [JAN. 

History. — According to the Grecian mythology, this is the animal which bore 
Europa over the seas to that country which derived from her its name. She was 
the daughter of Agenor, and princess of Phoenicia. She was so beautiful that 
Jupiter became enamored of her; and assuming the shape of a snow-white 
bull, he mingled with the herds of Agenor, while Europa, with her female at- 
tendants, were gathering flowers in the meadows. Europa caressed the beau- 
tiful animal, and at last had the courage to sit upon his back. The god now took 
advantage of her situation, and with precipitale stpps retired towards ti 
and crossed the sea with Europa upon his back, and arrived safe in Cre;e Some 
suppose she lived about 1552 years before the Christian Era. It is probable, 
however, that this constellation had a place in the Zodiae before the Greeks be- 
gan to cultivate a knowledge of the stars ; and that it was rather an invention oi 
the Egyptians or Chaldeans. Both the Egyptians and Persians worshiped a 
deity under this figure, by the name of Apis ; and Belzoni is said to have lound 
an embalmed bull in one of the notable sepulchres near Thebes. 

In the Hebrew Zodiac, Taurus is ascribed to Joseph. 



ORION. 

Whoever looks up to this constellation and learns its name, 
will never forget it. It is too beautifully splendid to need a 
description. When it is on the meridian, there is then above 
the horizon the most magnificent view of the celestial bodies 
that the starry firmament affords ; arid it is visible to all the 
habitable world, because the equinoctial passes through the 
middle of the constellation. It is represented on celestial 
maps by the figure of a man in the attitude of assaulting the 
Bull, with a sword in his belt, a huge club in his right hand, 
and the skin of a lion in his left, to serve for a shield. 

Manilius, a Latin poet, who composed five books on as- 
tronomy a short time before the birth of our Saviour, thus 
describes its appearance : — 

" First next the Twins, see great Orion rise. 
His arms extended stretch o'er half the skies ; 
His stride as large, and with a steady pace 
He marches on. and measures a vast space ; 
On each broad shoulder a bright star display'd, 
And three obliquely grace his hanging blade. 
In his vast head, immers'd in boundless spheres, 
Three stars, less bright, but yet as great, he bears, 
But farther off removed, their splendor's lost; 
Thus graced and arm'd he leads the starry host." 

The center of the constellation is midway between the 
poles of the heavens and directly over the equator. It is also 
about 8° W. of the solstitial colure. and comes to the meri- 
dian about the 23d of January. The whole number of visi- 
ble stars in this constellation is 78 ; of which, two aie of the 
first magnitude, four of the 2d, three of the 3d, and fifteen 
of the 4th. 

Those four brilliant stars in the form of a long square or 

What is the general appearance of the constell ition Orion ? When this constellation 
is on the meridian, what is the appearance of the starry firmament ? To w hom is it 
visible, and why ? How is Orion represented on celestial maps .' Describe its position. 
How is it situated with respect to the solstitial colure, and when is it on the meridian 1 
What remarkable stars form the outlines of the constellation ? 



MAP III.] ORION. 57 

parallelogram, intersected in the middle by the " Three 
Stars," or "Ell and Yard," about 25° S. of the Bull's horns, 
form the outlines of Orion. The two upper stars in the par- 
allelogram are about 15° N. of the two lower ones; and, 
being placed on each shoulder, may be called the epaulets 
of Orion. The brightest of the two lower ones is in the left 
foot, on the W., and the other, which is the least brilliant of 
the four, in the right knee. To be more particular; Bella - 
trix is a star of the 2d magnitude on the W. shoulder ; Be- 
telguese is a star of the 1st magnitude, 7*° E. of Bellatrix, 
onlhe E. shoulder. It is brighter than Bellatrix, and lies a 
little farther toward the north; and comes to the meridian 
30 minutes after it, on the 21st of January. These two form 
the upper end of the parallelogram. 

Rigel is a splendid star of the 1st magnitude, in the left 
(bot, on the W. and L5° S. of Bellatrix. Saiph is a star of 
tlie 3d magnitude, in the right knee, 81° E. of Rigel. These 
two form the lower end of the parallelogram. 



,; First in rank 



The martial star upon his shoulder flames 
A rival star illuminates his foot ; 
And on his girdie beams a luminary 
Which, in vicinity of o^ier stars, 
Might claim the proudHt honors." 

There is a little triangle of three small stars in the head 
of Orion, which forms a larger triangle with the two in his 
shoulders. In the middle of the parallelogram are three stars 
of the 2d magnitude, in the belt of Orion, that form a straight 
line about 3° in length from N. W. to S. E. They are usu- 
ally distinguished by the name of the Three Stains, because 
there are no other stars in the heavens that exactly resemble 
them in position and brightness. They are sometimes de- 
nominated the Three Kings, because they point out the 
Hyades and Pleiades on one side, and Sirius, or the Dog-star, 
on the oher. In Job they are called the Bands of Orion; 
while the ancient husbandmen called them Jacob's rod, and 
sometimes the Rake. The University of Leipsic, in 1807, 
gave them the name of Napoleon. But the more common 
appellation for them, including those in the sword, is the Ell 
and Yard. They derive the latter name from the circum- 
stance that the line which unites the " three stars " in the belt 
measures just 3° in length, and is divided by the central stai 



Describe the two upper ones in the group. Describe the two lower ones. Give a 
more particular description of the stars in the shoulder. How do you distinguish Be- 
telguese from Bellatrix ? When does Beteh'uese come to the meridian ? Describe the 
Ftars which form the lower end of the parallelogram. What stars do you observe in the 
head of Orion ? Describe the situation and appearance of the '"Ihree Stars." Why 
are they culled the three stars) What else are they denominated, and \ hy ? What 
names were given to them by the ancients ; What by the University of Leipsic ! What 
is the more familiar term for them, and whence is it derived - 



58 TICTURE OF THE HEAVENS. [.IAN. 

into two equal parts, like a yard-stick; thus serving as a 
graduated standard for measuring the distances of stars from 
each other. When, therefore, any star is described as being 
so many degrees from another, in order to determine the 
distance, it is recommended to apply this rule. 

It is necessary that the scholar should task his ingenuity only a few evenings in 
applying such a standard to the stars, before he will learn to judge of their rela- 
tive distances with an accuracy that will seldom vary a degree from the truth. 

The northernmost star in the belt, called Mintika, is less 
than 3° S. of the equinoctial, and when on the meridian, is 
almost exactly over the equator. It is on the meridian, the 
24th. of January.* 

The " three stars " are situated about S° W. of the solsti- 
tial colure, and uniformly pass the meridian one hour and 
fifty minutes after the seven stars. 

There is a row 7 of stars of the 4th and 5th magnitudes, S. 
of the belt, running down obliquely towards Saiph, which 
forms the sword. This row is also called the Ell because it 
is once and a quarter the length of the Yard or belt. 

A very little w T ay below Thabit, in the sword, there is a 
nebulous appearance, the most remarkable one in the hea- 
vens. With a good telescope an apparent opening is disco- 
vered, through which, as through a window, we seem to get 
a glimpse of other heavens, and brighter regions beyond. 

As the telescope extends our knowledge of the stars and greatly increases 
their visible number, we behold hundreds and thousands, which, but for this 
. almost divine improvement of our vision, had forever remained, unseen by us, 
in an unfathomable void. 

A star in Orion's sword, which appears single to the unassisted vision, is mul- 
tiplied into six by the telescope; and another, into twelve. Galileo found SO in 
the belt, 21 in a nebulous star in the head, and about 500 in another part of Orion, 
within the compass of one or two decrees. Dr. Hook saw 78 stars in the Pleiades, 
and Rheita, with a better telescope, saw about 200 in the same cluster and more 
than 2000 in Orion. 

About 9° W. of Bellatrix are eight stars, chiefly of the 4th 
magnitude, in a curved line running N. and S. with the con- 
cavity toward Orion; these point out the skin of the lion in 
his left hand. Of Orion, on the whole, we may remark with 
Eudosia: — 

" He who admires not, to the stars is blind." 
History. — According to some authorities, Orion was the son of Neptune and 
queen Euryale, a famous Amazonian huntress, and possessing the disposition of 

* Though the position of this star, with respect to the equator, i3 the same at all 
times whether it be on the meridian or in the horizon ; yet it appears to occupy thia 
position, only, when it is on the meridian. 

How may the distances of the stars from each other be measured by reference to the 
Yard •' How are the three stars situated with respect to the solstitial colure, and how 
with respect to the seven stars? Describe the stars which form the sword of Orion 
What else is this row railed? Describe the nebulous appearance which is visible in 
this cluster. Wliat other discoveries has the telescope made in tins constcltdlu)n 1 
What stars about 9° W. of Bellatrix ? 



MAP. III.] ORION. 59 

his mother, he became tne greatest nunter m the world, and even boasted that 
there was not an animal on earth which he could not conquer. To punish this 
vanity, it is said that a scorpion sprung up out of the earth and bit his foot, that 
he died ; and that at the request of Diana he was placed among the stars directly 
opposite to the Scorpion that caused his death. Others say that Orion had no 
mother, but was the gift of the gods, Jupiter, Neptune, and Mercury, to a peasant 
of Boeotia.as a reward of piety, and that he was invested with the power of walk- 
ing over the sea without wetting his feet. In strength and stature he surpassed 
all other mortals. He was skilled in the working of iron, from which he fabri- 
cated a subterranean palace for Vulcan ; he also walled in the coasts of Sicily 
against the inundations of the sea, and built thereon a temple to its gods. 
"Orion was betrothed to the daughter of OZnopion, but he, unwilling to give up 
his daughter, contrived to intoxicate the illustrious hero and put out "his eyes on 
the seashore where he had laid himself, down to sleep. Orion, finding himself 
blind when he awoke, was conducted by the sound to a neighboring forge, where 
he placed one of the workmen on his back, and, by his "directions, went to a 

Slace where the rising sun was seen with the greatest advantage. Here he turned 
is face toward the luminary, and, as it is reported, immediately recovered his 
sight, and hastened to punish the perfidious cruelty of OZnopion. 

The daughters of Orion distinguished themselves as much as their father; 
and, when the oracle had declared that Bceotia should not be delivered from a 
dreadful pestilence, before two of Jupiter's children were immolated on the 
altars, they joyfully accepted the offer, and voluntarily sacrificed themselves for 
the good o'f their country. The deities of the infernal regions were struck at the 
patriotism of the two females, and immediately two stars were seen to ascend 
up from the earth, still smoking with their blood, and they were placed in the 
heavens in the form of a crown. Ovid says their bodies'were burned by the 
Thebans. and that two persons arose from their ashes, whom the gods soon after 
changed into constellations. 

As" the constellation Orion, which rises at noon about the 9th day of March, 
and sets at noon about the 21st of June, is generally supposed to be accompanied, 
at its rising, with great rains and storms, it became extremely terrible to mari- 
ners, in the early adventures of navigation. Virgil, Ovid, and Horace, with some 
of the Greek poets, make mention of this. 

Thus Eneas accounts for the storm which cast him on the African coast on his 
way to Italy : — 

"To that blest shore we steer'd our destined way, 
When sucjden, dire Orion rous'd the sea ; 
All charg'd with tempests rose the baleful star. 
And on our navy pour'd his wat'ry war." 

To induce him to delay his departure, Dido's sister advises her to 

'' Tell him, that, charg'd with deluges of rain, 
Orion rages on the wintry main." 

The name of this constellation is mentioned in the books of Job and Amos, ana 

in Homer. The inspired prophet, penetrated like the psalmist of Israel with 

the omniscience and power displayed in the celestial glories, utters this sublime 

injunction : " Seek Him that maketh the seven stars and Orion, and turnerh tUe 

shadow of death into morning." Job also, with profound veneration, adores His 

awful majesty who " commandeth the sun and sealeth up the stars ; who alone 

Bpreadeth out the heavens, and maketh Arcturus. Orion, and Pleiades, and the 

chambers of the south :" and in another place, the Almighty demands of him — 

" Knowest thou the ordinances of heaven ? Canst thou bind the sweet influences 

of the Pleiades, or loose the bands of Orion ; canst thou bring forth Mazzarolh in 

his season, or canst thou guide Arcturus with his sons V 

Cab.net supposes that Mazzaroth is here put for the whole order of celestial 

the Zodiac, which, by their appointed revolutions, produce the various 

seasons of the year, and the regular succession of day and night. Arcturus is 

the name of the principal star "in Bootes, and is here put for the constellation 

The expression, his sons, doubtless refers to Aslerion and Chara.the 

hounds, with which he seems to be pursuing the Great Bear around tho 

North pole. 

'owing lines are copied from a work entitled " Astronomical Recrea- 
en, of Pennsylvania, to whom the author is indebted tor many 
■oui'erning the mytholo y of the anient 



i 



60 PICTURE OF THE HEAVENS. ["JAN. 

" When chilling winter spreads his azure skies. 

Behold Orion's giant form arise ; 

His golden girdle glitters on the siihr ; 

And the broad falchion beams in splendor bright ; 

A lion's brindled hide his bosom shields, 

And his right hand a ponderous weapon wields. 

The River's shining streams beneath him pour. 

And angry Taurus rages close before ; 

Behind him Procyon barks, and Sirius growls, 

While full in front, the monster Cetus howls. 

See bright Capella. and Medusa there, 

With horrid serpents hissing through her hair ; 

See Cancer too, and near the Hydra dire, 

With roaring Leo, filled with furious fire. 

The timid Hare, the Hove with olive green, 

And Aries, fly in terror from the scene ; 

The warrior Perseus gazes from above, 

And the Twin offspring of the thunderer Jove. 

Lo ! in the distance. Cassiope fair 

In state reposes on her golden chair ; 

Her beauteous daughter, bound, before her stands, 

And vainly strives to free her fettered hands ; 

For aid she calls on royal Cepheus near, 

But shrieks from her reach not her father's ear. 

See last of all. around the glowing pole, 

With shining scales, the spiry Dragon roll 

A grizzly Bear on either side appears, 

Creeping with lazy motion 'mid the stars." 
These lines are easily committed to memory, and would assist the pupil in 
recalling the names of the constellations in this very interesting portion of the 
heavens. 



LEPUS. 

The Hare. — This constellation is situated directly south of 
Orion, and comes to the meridian at the same time ; namely, 
on the 24th of January. It has a mean declination 18° S., 
and contains 19 small stars, of which, the four principal ones 
are of the 3d magnitude. It may be readily distinguished 
by means of four stars of the 3d magnitude, in the form of 
an irregular square, or trapezium. 

Zeta. of the 4th magnitude, is the first star, and is situated 
in the back, 5° S. of Saiph, in Orion. About the same dis- 
tance below Zeta are the four principal stars, in the legs and 
feet. These form the square. They are marked Alpha, 
Beta. Gamma, Delta. Alpha, otherwise called Arneb, and 
Beta form the N. W. end of the trapezium, and are about 
3° apart. Gamma and Delta form the S. E. end, and are 
about 2|° apart. The upper right-hand one, which is Arneb, 
is the brightest of the four, and is near the center of the 

Where is the constellation of the Hare situated ? When does it come to the meri- 
dian ? What is the whole number of its stars ? What is the magnitude of its principal 
ones' How may it be distinguished ? In what part of the animal are these stars 
placed ? Describe the principal star in Lepus. What are the distance and direction of 
the square from Zeta? Describe the stars at each end of this square. Which is 
the brightest of the four ? 



i»IAP III. J COLUMBA ERIHANUS. 61 

constellation. Four or five degrees S. of Rigel are four 
very minute stars, in the ears of the Hare. 

History. — This constellation is situated about 18° west of the Great Dog, which, 
from the motion of the earth, seems to be pursuing it, as the Greyhounds do the 
Bear, round the circuit of the skies. It was one of those animals which Orion is 
said to have delighted in hunting, and which, for this reason, was made into a 
constellation and" placed near him among the stars. 



COLUMBA. 

Noah's Dove. — This constellation is situated about .16° 
S. of the Hare, and is nearly on the same meridian with 
the " Three Stars," in the belt of Orion. It. contains only 10 
stars ; one of the 2d, one of the 3d, and two of the 4th mag- 
nitudes; of these, Phaet and Beta are the brightest, and are 
about 2i° apart. Phaet. the principal star, lies on the right 
and is the highest of the two ; Beta maybe known by means 
of a smaller star just east of it, marked Gamma. A line 
drawn from the easternmost star in the belt of Orion. 32° 
directly south, will point out Phaet ; it is also 11*° S. of the 
lower left-hand star in the square of the Hare, and makes 
with Sirius and Naos, in the ship, a large equilateral triangle. 

History. — This constellation is so called in commemoration of the dove which 
Noah "sent forth to see if the waters were abated from off the face of the 
ground." after the ark had rested on mount Ararat. " And the dove came in to 
him in the evening, and Io, in her mouth was an olive leaf plucked off 

'' The surer messenger, 

A dove sent forth once and again to spy 

Green tree or ground, whereon his foot may light : 

The second time returning, in his bill 

An olive leaf he brings, pacific sign !" 



ERIDANUS. 

The River Po. — This constellation meanaers over a large 
and very irregular space in the heavens. It is not easy, nor 
scarcely desirable, to trace out all its windings among the 
stars. Its entire length is not less than 130°; which, for 
the sake of a more easy reference, astronomers divide into 
two sections, the northern and the southern. That part of 
it which lies between Orion and the Whale, including the 
great bend about his paws, is distinguished by the name of 
the Nortliem stream; the remainder of it is called the 
Southern stream. 

The Northern stream commences near Rigel, in the loot of 

Are these all the stars that are visible in this constellation ? Describe the situation 
of Noah's Dove. How many stars does it contain, and what are the principal : Which 
of thesr are the brightest, an. i how situated ' How may Beta b-: known ' \\ hat is 
the position of Phaet with regard to Orion ? Describe the general form ot the constel- 
lation Eridanus. What is its entire length, and how is it divided' By what names 
are these sections distinguished 1 What are the course and distance ol the Northern 
■ Btream.i 



b'2 PICTURE OF THE HEAVENS [JAN. 

Orion, and flows out westerly, in a serpentine course nearly 
40°, to the Whale, where it suddenly makes a complete cir- 
cuit and returns back nearly the same distance toward its 
source, but bending gradually down toward the south, when 
it again makes a similar circuit to the S. W. and finally dis- 
appears below the horizon. 

West of Rigel there are five or six stars of the 3d anrl 4th magnitudes, arching 
up in a semicircular form, and marking the first bend of the northern stream. 
About 8° below these, or 19° W. of Rigel, is a bright star of the 2d magnitude / 
in the second bend of the northern stream, marked Gumma. This star cul- 
minates 13 minutes after the Pleiades, and one hour and a quarter before Rijgel 
Passing Gamma, and a smaller s'.ar west of it, there are four stars nearly in a 
row. which bring us to the breast of Cetus. 8° N. of Gamma, is a small star 
turned Kied, which is thought by some to be considerably nearer the earth than 
Sir ius. 

Theemim, in the southern stream, is a star of the 3d magnitude, about 17° S. 
W. of the square in Lepus. and may be known by means of a smaller star. 1° ■ 
above it. Achernar is a brilliant star of the 1st magnitude, in the extremity of 
the southern stream ; but having 58° of S. declination, can never be seen in this 
latitude. 

The whole number of stars in this constellation is 84; of 
which, one is of the 1st magnitude, one of the 2d. and eleven 
are of the 3d. Many of these cannot be pointed out by ver- 
bal description; they must be traced from the map. 

History. — Eridanus is the name of a celebrated river in Cisalpine Gaul, also 
called Padus. Its modern name is Po. Virgil calls it the king of rivers. The 
Latin poets have rendered it memorable from its connection with the fable of Phae- 
ton, who, being a son of Phoebus and Ciymene, became a favorite of Venus, who 
intrusted him with the care of one of her temples. This favor of the a 
made him vain, and he sought of his father a public and incontestable sign of his 
tenderness, that should convince the world of his origin. Phoebus, a I ft r some 
hesitation, made oath that he would grant him whatever he required, and no 
sooner was the oath uttered, than — 

"The youth, transported, asks without delay. 

To guide the sun's bright chariot for a day. 

The god repented of the oath he took, 

For anguish thrice his radiant head he shook ;-- 

My son, says he, some other proof require, 

Rash was my promise, rash was thy desire — 

Not Jove himself, the ruler of the sky, 

That hurls the three-forked thunder from above, 

Dares try his strength ; yet. who as strong as Jove 1 

besides, consider what impetuous force 

Turns stars and planets in a different course. 

I steer against their motions ; nor am I 

Borne back by all the current of the sky : 

But how could you resist the orbs that roll 

In adverse whirls, and stem the rapid | 
Phoebus represented the dangers to which he would 1 ' n. He 

undertook the aerial journey, and the explicit directions of his father wi 
gotten. No sooner had Phaeton received the reins than he betrayed his ig- 
norance of the manner of guiding the chariot. The flyi me sen- 
sible of the confusion of their driver, and immediately departed from the usual 
track. Phaeton repented too late of his rashness, ami already heaven and earth 

Describe its first bend. Describe the portion of Gamma, and tell when it i i 
(be meridian. What stars are be, 

about 8" above Gamma, and what is its distance from the re; h that of 

! escribe the situ 

■ What is the whole number of stars in this constellation .' Wfc* * »* 
magnitude of the principal oiks > 



MAP. III.] AURIGA. 03 

were threatened with a universal conflagration as the consequence, when Jupi- 
ter, perceiving the disorder of the horses, struck the driver with a thunderbolt, 
and hurled him headlong: from heaven into the river Eridanus. His body, con- 
sumed with fire, was found by the nymphs of the place, who honored him with 
a decent burial, and inscribed this epitaph upon his tomb :— 
l - Hie situs est Phaeton, currus auriga paterni : 
Queue si non tenuit, mugnis tai/ien excidit ausis." 
His sisters mourned his unhappy end, and were changed by Jupiter into 
poplars. 

u All the long night their mournful watch they keep, 
And all the day stand round the tomb and weep."— Ovid. 
It is said the tears which they shed turned to amber, with which the Phoeni- 
cians and Carthaginians carried on in secrecy a most lucrative trade. The great 
heat produced on the occasion of the sun's departing out of his usual course, is 
said to have dried up the blood of the Ethiopians, and turned their skins black ; 
and to have produced sterility and barrenness over the greater part of Libya. 
" At once from life and from the chariot driven, 
Th' ambitious boy fell thunderstruck from heaven." 
******** 
•' The breathless Phaeton, with flaming hair, 
Shot from the chariot like a falling star, 
That in a summer's evening from the top 
Of heav'n drops down, or seems at least to drop, 
Till on the Po his blasted corpse was hurl'd, 
Far from his country, in the western world." 
The fable of Phaeton evidently alludes to some extraordinary heats which 
were experienced in a very remote period, and of which only this confused tra- 
dition has descended to later times. 



AURIGA. 

The Charioteer, called also the Wagoner, is represent- 
ed on the celestial map by the figure of a man in a reclining 
posture, resting one foot upon the horn of Taurus, with a 
goat and her kids in his left hand, and a bridle in his right. 

It is situated N. of Taurus and Orion, between Perseus 
on the W. and the Lynx on the E. Its mean declination is 
45° N.; so that when on the meridian, it is almost directly 
overhead in New England. It is on the same meridian 
with Orion, and culminates at the same hour of the night. 
Both of these constellations are on the meridian at 9 o'clock 
on the 24th of January, and lhour and 40 minutes east of il 
on the 1st of January. 

The whole number of visible stars in Auriga, is 66, includ- 
ing one of the 1st and one of the 2d magnitude, which mark 
the shoulders. Capella is the principal star in this constel- 
lation, and is one of the most brilliant in the heavens. It 
takes its name from Capella, the goat, which hangs upon the 
left shoulder. It is situated in the west shoulder of Auriga, 



How is the constellation Auriga represented? Where is it situated? What is its 
mean declination, and what its position on the meridian ? How is it situated in re- 
spect to Orion ? When ;ne these constellations on the meridian ? What is the whole 
Rumher of visible stars inAuriea? How many of the 1st and 2d magnitude) What 
is the name of the principal star, and whence derived ? Where is this situated? 



64 PICTURE OF THE HEAVENS. [Jan. 

24° E. of Algol, and 28° N. E. of the Pleiades. It may be 
known by a little sharp-pointed triangle formed by three stars, 
3° or 4° this side of it. on the left, "it is also 18° N. of El 
Nath, which is common to the northern horn of Taurus, and 
the right foot of Auriga. Capella comes to the meridian on 
the 19th of January, just 2\ minutes before Rigel, in the foot 
of Orion, which it very much resembles in brightness. 

Menkalina, in the east shoulder, is a star of the 2d magnitude. 7k° E. of Capella, 
and culminates the next minute after Betelguese, 37§° S. of it. Theta, in the 
right arm, is a star of the 4th magnitude, 8° directly south of Menkalina. 

It may be remarked as a curious coincidence, that the two stars in the shoul- 
ders of Auriga are of the same magnitude, and just as far apart as those in Orion, 
and opposite to them. Again, the two stars in the shoulders of Auriga, with the 
two in the shoulders of Orion, mark the extremities of a long, narrow parallelo- 
gram, lying N. and S., and whose length is just five times its breadth. Also, the 
two stars in Auriga, and the two in Orion, make two slender and similar triangles, 
both meeting in a common point, half w T ay between them at El Nath, in the north 
ern horn of Taurus. 

Delta, a star of the 4th magnitude in the head of Aurisa, is about 9° N. of the 
two in the shoulders, with which it makes a triansrle. about half the height of 
those just alluded to, with the vertex at Delta. The two stars in the shoulders 
are therefore the base of two similar triangles, one extending about 9° N.. to the 
head, the other 18° S., to the heel, on the top of the horn : both figures together 
resembling an elongated diamond. 

Delta in the head. Menkalina in the right shoulder, and Theta in the arm of 
Auriga, make a straight line with Betelguese in Orion, Delta in the square of the 
Hare, and Beta in Noah's Dove ; all being very nearly on the same meridian. 
48 W. of the solstitial colure. 

(i See next the Goatherd with his kids ; he shines 
With seventy stars, deducting only four. 
Of which Capella never sets to us.* 
And scarce a star with equal radiance beams 
Upon the earth : two other srars are seen 
Due to the second order." — Eudosia. 
History. — The Greeks give various accounts of this constellation : some sup- 
pose it to be Erichthonius, the fourth king of Athens, and son of Vulcan and 
Minerva, who awarded him a place among the constellations on account of hia 
many useful inventions. He was of a monstrous shape. He is said to have in- 
vented chariots, and to have excelled all others in the management of horses. In 
allusion to this, Virgil has the following lines : — 

"Primus Erichthonius currus et quatuor ausus 
Jungere equos, rapidisque rotis insistere victor." 

Georgic. Lib. iii. p. 113. 
" Bold Erichthonius was the first who join'd 
Four horses for the rapid race designed, 
And o'er the dusty wheels presiding sate."— Dryden. 
Other writers say that Bootes invented the chariot, and that Aurisra was the 
eon of Mercury, and charioteer to OEnomaus, king of Pisa, and so experienced, 
that he rendered his horses the swiftest in all Greece. But as neither of these 
fables seems to account for the goat and her kids, it has been supposed that they 
refer to Amalthaea and her sister Melissa, who fed Jupiter, during his infancy 

* In the latitude of London ; but in ttfe latitude of New Encland, Capella disappears 
below the horizon, in the N. N. \V., for a few hours, and then reappears in (he N. 



How may it be known? "What are its distance and direction from El Nath. in the 
horn of Taurus ? When does Caoella come to the meridian? Describe the star in the 
east shoulder of Auriga. Describe Theta. What curious coincidence exists between 
the stars in the shoulders of Auriga and those in the shoulders of Orion ? Describe the 
situation of Delta. The tioo stars in the shoulders of Auriga form the base of two tri- 
angles; please describe them. What stars in Auriga, Orion, the Hare, and the Dare, 
are on the same meridian ? Hoiv far is this line of stars west of t/ie solstitial colure J 



MAP VI.] CAMELOPARDALUS. THE LYNX. 65 

with goat's milk, and that, as a reward for their kindness, they were placed in 
the heavens. But there is no reason assigned for their being placed in the arms 
of Auriga, and the inference is unavoidable, that mythology is at fault on this 
point. 

Jamieson is of opinion that Auriga is a mere type or scientific symbol of the 
beautiful fable of Phaeton, because he was the attendant of Phoebus at that re- 
mote period when Taurus opened the year. 



CAMELOPARDALUS. 

.The Camelopard. — This constellation was made by He- 
velius out of the unformed stars which lay scattered between 
Perseus, Auriga, the head of Ursa Major, and the Pole Star. 
It is situated directly N. of Auriga and the head of the Lynx, 
and occupies nearly all the space between these and the pole. 
It contains 58 small stars ; the five largest of which are only 
of the 4th magnitude. The principal star lies in the thigh, 
and is about 20° from Capella, in a northerly direction. It 
marks the northern boundary of the temperate zone; being 
less than one degree S. of the Arctic circle. There are two 
other stars of the 4th magnitude near the right knee. 12° 
N. E. of the first mentioned. They may be known by their 
standing 1° apart and alone. 

The other stars in this constellation are too small, and too 
much scattered to invite observation. 

History.— The Camelopard is so called from an animal of that name, peculiar 
to Ethiopia. This animal resembles both the camel and the leopard. Its body 
is spotted like that of the leopard. Irs neck is about seven feet long, its fore and 
hind legs, from the hoof to the second joint, are nearly of the same length ; but 
from the second joint of the legs to the body, the fore legs are so long in compar- 
ison with the hind ones, that ho person could sit upon its back, without instantly 
eliding off as from a horse that stood up on his hind feet. 



CHAPTER IY. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARF 
ON THE MERIDIAN IN FEBRUARY. 

THE LYNX. 

The constellation of the Lynx, like that of the Camelopard, 
exhibits no very interesting features by which it can be dis- 
tinguished. It contains only a moderate number of inferior 
stars, scattered over a large space N. of Gemini, and between 
Auriga and Ursa Major. The whole number is 44, includ. 

Of what was the Camelopard made ? Where is it situated ? What is the whole num- 
ber of stars ? What is the magnitude of the largest > What are the name and position 
of the principal one? Where are the other principal stars situated' How may they 
b* known? Whence does it derive i\s namei W ".at is the situation of the Lynx 1 
What are the number and magnitude of its stars J 

c* 



66 PICTURE OF THE HEAVENS. [FEB. 

ing only three that are so large as the 3d magnitude. The 
largest of these, near the mouth, is in the solstitial colure, 
14i° N. of Menkalina, in the E. shoulder of Auriga. The 
other two principal stars are in the brush of the tail, 3h° S. 
W. of another star of the same brightness in the mouth of 
the Lesser Lion, with which it makes a small triangle. Its 
center is on the meridian at 9 o'clock on the 23d, or at hall- 
past 7 on the 1st of February. 

History.— This constellation takes its name from a wild beast which is said to 
be of the genus of the wolf. 



GEMINI. 

The Twins. — This constellation represents, in a sitting 
posture, the twin brothers, Castor and Pollux. 

Gemini is the third sign, but fourth constellation in the 
order of the Zodiac, and is situated south of the Lynx, be- 
tween Cancer on the east, and Taurus on the west. The 
orbit of the earth passes through the center of the constella- 
tion. As the earth moves round in her orbit from the first 
point of Aries to the same point again, the sun, in the mean 
time, will appear to move through the opposite signs, or 
those which are situated right over against the earth, on the 
other side of her orbit. 

Accordingly, if we could see the stars as the sun appeared 
to move by them, we should see it passing over the constella- 
tion Gemini between the 21st of June and the 23d of July; 
but we seldom see more than a small part of any constella- 
tion through which the sun is then passing, because the fee- 
ble luster of the stars is obscured by the superior effulgence 
of the sun. 

When the sun is just entering the outlines of a constellation on the east, its 
western limit may be seen in the morning twilight, just above the rising sun. 
So when the sun has arrived at the western limit of a constellation, the eastern 
part of it may be seen lingering in the evening twilight, just behind the setting 
sun. Under other circumstances, when the sun is said "to be in, or to enter, a 
particular constellation, it is to be understood that that constellation is not then 
visible, but that those opposite to it are. For example : whatever constellation 
sets with the sun on any day, it is plain that the one opposite to it must be then 
rising, and continue visible through the night. Also, whatever constellation rises 
and sets with the sun to-day, will, six months hence, rise at sun-setting, and set 
at sun-rising. For example : the sun is in the center of Gemini about the 6th of 

Describe the position of the largest. Describe the position of the other two principal 
stars. What are their distance and direction from the one in the head? When is its 
center on the meridian? Describe the position and appearance of the Twins. What 
is the relative position of Gemini among the signs and constellations of the Zodiac ? 
How is the orbit of the earth situated, with respect to these constellations ? How do 
the sun and earth appear to move through these signs? When does the sun appear to 
pass through the constellation Gemini? Do we usually see the constellations while the 
sun is passing through them? Under what circumstances canioe se-e some part of 
them.1 When the, sun is in or entering any cons:/ Hnti'm, arc she opposite constellations 
visible or not ) If a constellation rise with the sun to-day, how icill it rise six months 
hence 1 Gice an example. 



MAP III. J GEMINI. 67 

July, and must rise and set with it on that day ; consequently, six months from 
that time, or about the 4th of January, it will rise in the east, just when the sun 
is setting in the west, and will come to the meridian at midnight ; being then ex- 
actly opposite to the sun. 

Now as the stars gain upon the sun at the rate of two hours every month, it 
follows that the center of this constellation will, on the 17th of February, come to 
the meridian three hours earlier, or at 9 o'clock in the evening. 

It would be a pleasant exercise for students to propose questions to each other, 
somewhat like the following: — What zodiacal constellation will rise and set with 
the sun to-day/? What one will rise at sun-setting"? What constellation is 
three hours high at sun-set, and where will it be at 9 o'clock'? What constella- 
tion rises two hours before the sun 7 How many days or months hence, and at 
what hour of the evening or morning, and in what part of the sky shall we see 
the constellation whose center is now where the sun is 1 &c, &c. 

In solving these and similar questions, it may be remembered that the sun is in 
the vernal equinox about the 21st of March, from whence it advances through 
one sign or constellation every succeeding month thereafter; and that each con- 
> stellation is one month in advance of the sign of that name : wherefore, reckon 
Pisces in March, Aries in April, Taurus in May. and Gemini in June, &c. ; be- 
ginning with each constellation at the 21st, or 22d of the month. 

Gemini contains 85 stars, including two of the 2d, three 
of the 3d, and six of the 4th magnitudes. It is readily re- 
cognized by means of the two principal stars, Castor and 
Pollux, of the 1st and 2d magnitudes, in the head of the 
Twins, about 4£° apart. 

There being only 11 minutes' difference in the transit of 
these two stars over the meridian, they may both be consid- 
ered as culminating at 9 o'clock about the 24th of February. 
Castor, in the head of Castor, is a star of the 1st magnitude, 
41° N. W. of Pollux, and is the northernmost and the bright- 
est of the two. Pollux, is a star of the 2d magnitude; in 
the head of Pollux, and is 4| S. E. of Castor. This is one 
of the stars from which the moon's distance is calculated in 
the Nautical Almanac. 

" Of the famed Ledean pair, 

One most illustrious star adorns their sign, 
And of the second order shine twin lights." 

The relative magnitude or brightness of these stars has 
undergone considerable changes at different periods ; whence 
it has been conjectured by various astronomers that Pollux 
must vary from the 1st to the 3d magnitude. But Herschel, 
who observed these stars for a period of 25 years, ascribes 
the variation to Castor, which he found to consist of two 
stars, very close together, the less revolving about the larger 
once in 342 years and two months. 

Bradly and Maskelyne found that the line joining the two stars which form 
Castor was, at all time's of the year, parallel to the line joining Castor and Pollux ; 
and that both of the former move around a common center between them, in 

If a constellation come to the. meridian at midnight to-day, hoio long before it will 
conic to the meridian at 9 o'clock in the evening? If the constellation < iemini come to 
the ?/i£?idian at midnight, on the 4th of January, when will it culminate at 9 o'clock'! 
What is the number ot' stars in Gemini? By what means is it readily recognized? 
When do these stars culminate? Describe Castor. Describe Pollux. For what pur- 
pose is it observed at sea ? Is the brightness of these two stars always the Buaae ? Who 
ascribes this variableness to Castor, and for what reason ! 



68 PICTURE OF THE HEAVENS. [FEB. 

orbits nearly circular, as two balls attached to a rod wquld do, if suspended by a 
strinsr affixed to the center of gravity between them. 

'• These men," says Dr. Bowditch, " were endowed with a sharpness of vision, 
and a power of penetrating into space, almost unexampled in the history of as- 
tronomy." 

About 20° S. W. of Castor and Pollux, and in a line nearly parallel with them, 
is a row of stars 3° or 4° apart, chiefly of the 3d and 4th magnitudes, which dis- 
tinguish the feet of the twins. The brightest of these is Alhena, in Pollux's-upper 
foot ; the next small star S. of it. is in his other foot : the two upper stars in the 
line next above Gamma, mark Castor's (eet. 

Tiiis row of feet is nearly two thirds of the distance from Pollux to Betelguese 
in Orion, and a line connecting them will pass through Alhena, the principal star 
in the feet. About two thirds of the distance from the two in the head to those 
in the feet, and nearly parallel with them, there is another row of three stars 
about 6° apart, which mark the knees. 

There are, in this constellation, two other remarkable parallel rows, lying at 
right angles with the former; one, leading from the head io the foot of Castor, 
the brightest star being in the middle, and in the knee : the other, leading from 
the head to the foot of Pollux, the brightest star, called Wasat, being in the body, 
and Zeta, next below it, in the knee. 

Wasat is in the ecliptic, and very near the center of the constellation. The 
two stars. Mu and Tejar, in the northern foot, are also very near the ecliptic ; Te- 
jat is a small star of between the 4th and 5tn magnitudes, 2' 1 YV. of Mu, and de- 
serves to be noticed because it marks the spot of the summer solstice, in the 
tropic of Cancer, just where the sun is on the longest day of the year, and is, 
moreover, the dividing limit between the torrid and the N. temperate zone. 

Propus, also in the ecliptic, 2£° W. of Tejat. is a star of only the 5th magnitude, 
but rendered memorable as being the star which served for many years to de- 
termine the position of the planet Herschel, after its first discovery. 

Thus as we pursue the study of the stars, we shall find continually new and 
more wonderful developments to engage our feelings and reward our labor. 
We shall have the peculiar satisfaction of reading the same volume that was 
spread out to the patriarchs and poets of other ages, of admiring what they ad- 
inirca, and of being led as they were led, to look upon these lofty mansions of 
being as having, above them all. a common Father with ourselves. '• who ruleth 
in the armies of heaven, and bringeth forth their hosts by number." 

History. — Castor and Pollux were twin brothers, sons of Jupiter, by Leda, 
the wife of Tyndarus, king of Sparta. The manner of their birth was very sin- 
gular. They were educated at Pallena, and afterwards embarked with Jason in 
the celebrated contest for the golden fleece, at Colchis; on which occasion they 
behaved with unparalleled courage and bravery. Pollux distinguished himseLi' 
by his achievements inarms and personal prowess, and Castor in equestrian 
exercises and the management of horses; whence they are represented, in the 
. temples of Greece, on white horses, armed with spears, riding side by side, their 
heads crowned with a petasus. on whose top glittered a star. Among the an- 
cients, and especially among the Romans, there prevailed a superstition that 
Castor and Pollux often appeared at the head of their armies, and led on their 
troops to battle and to victory. 

" Castor and Pollux, first in martial force, 
One bold on foot, and one renown'd for horse. 
Fair Leda's twins in time to stars decreed, 
One fought on foot, one curb'd the fiery steed." — Virgil. 
"Castor alert to tame the foaming steed, 

And Pollux strong to deal the manly deed."— Martial. 
The brothers cleared the Hellespont and the neighboring seas from pirates 
after their return from Colchis; from which circumstance they have ever since 
been regarded as the friends and protectors of navigation. In the Argonautic 
expedition, during a violent storm, it is said two flames of fire were seen to play 
around their heads, and immediately the tempest ceased, and the sea was calm. 

Describe the stars which mark the feet of the Twins. Specify the stars in each. How 
is this row situated with respect to Orion ? Describe the second row of sta-s in this 
constellation. Are there yet other rows in this constellation? Describe them. Wluit 
is tiie position of Wasat? Two otlier stars are very near the ecliptic; mention thevi. 
Describe the position of Tejat. Give a description of the star Propus. 



MAP III. J CANIS MINOR. 69 

From this circumstance, the sailors inferred, that whenever both fires appeared 
m the sky, it would be fair weather; but when only one appeared, there would 
be storms. 

St. Paul, after being wrecked on the island of Melita, embarked for Rome ' : in 
a ship whose sign was Castor and Pollux ;'•' so formed, no doubt, in accordance 
with the popular belief that these divinities presided over the science and safety 
of navigation. 

They were initiated into the sacred mysteries of Cabiri, and into those of Ceres 
at Eleusis. They were invited to a feast at which Lynceus and Idas were going 
to celebrate their nuptials with Phoebe and Telaria, the daughters of Leucippus, 
brother to Tyndarus. They became enamored of the daughters who were 
about to be married, and resolved to supplant their rivals: a battle ensued, in 
which Castor killed Lynceus, and was himself killed by Idas. Pollurc revenged 
the death of his brother by killing Idas; but being himself immortal and most 
tenderly attached to his deceased brother, he was unwilling to survive him ; he 
therefore entreated Jupiter to restore him to life, or to be deprived himself of 
immortality : wherefore, Jupiter permitted Castor, who had been slain, to share 
the immortality of Pollux; and consequently as long as the one was upon earth, 
so long was the other detained in the infernal regions, and they alternately lived 
and died everyday. Jupiter also further rewarded their fraternal attachment 
by changing them both into a constellation under the name of Gemini, Twins, 
which, it is strangely pretended, never appear together, but when one rises the 
other sets, and so on alternately. 

" By turns they visit this ethereal sky, 

And live alternate, and alternate die." — Homer. 
"Pollux, offering his alternate life, 
Could free his brother, and could daily go 
By turns aloft, by turns descend below." — Virgil. 
Castor and Pollux were worshiped both by the Greeks and Romans, who 
sacrificed white lambs upon their altars. In the Hebrew Zodiac, the constella- 
tion of the Twins refers to the tribe of Benjamin. 



CANIS MINOR. 

The Little Dog. — This small constellation is situated 
about 5° N. of the equinoctial, and midway between Canis 
Major and the Twins. It contains 14 stars, of which two 
are very brilliant. The brightest star is called Procyon. 
It is of the 1st magnitude, and is about 4° S. E. of the next 
brightest, marked Gomelza, which is of the 3d magnitude. 

These two stars resemble the two in the head of the Twins. 
Procyon, in the Little Dog, is 23° S. of Pollux in Gemini, 
and Gomelza is about the same distance S. of Castor. 

A great number of geometrical figures may be formed of 
the principal stars in the vicinity of the Little Dog. For ex- 
ample ; Procyon is 23° S. of Pollux, and 26° E. of Betelguese, 
and forms with them a large right-angled triangle. Against 
Procyon is equidistant from Betelguese and Sirius, and forma 
with them an equilateral triangle whose sides are each about 
2(3°. If a straight line, connecting Procyon and Sirius, be 
produced 23° farther, it will point out Phaet, in the Dove. 

Describe the situation of Canis Minor. What is its whole number of stars? What is 
the magnitude of its principal ones? What is the brightest one called, and how i.-- it 
situated' What other stars do Procyon and Gomelza resemble? What are the dis- 
tance anddirection of Procyon from Pollux? Of Gomelza from Castor? What are their 
distance and direction from Castor and Pollux ? What kind of* figures may be formed 
uf the stars in the neighborhood of the Little Dog ? Give some examples. 



70 PICTURE OF THE HEAVENS. [FEB 

Procyon is often taken for the name of the Little Dog, or 
for the whole constellation, as Sirius is for the greater one; 
hence it is common to refer to either of these constellations 
\>y the name of its principal star. Procyon comes to the 
meridian 53 minutes after Sirius. on the 24th of February; 
although it rises, in this latitude, about half an hour before 
it. For this reason, it was called Procyon, from two Greek 
words which signify (Ante Cants') "before the dog. ; ' 

l> Canicula, fourteen thy stars ; but far 
Above them all, illustrious through the skies. 
Beams Procyon ; justly by Greece thus called 
The bright forerunner of the greater D is.'' 

History.— The Little Do<r. according to Greek fable, is one of Orion's hounus. 
Some suppose it refers to the Egyptian sod Anubis, which was represented with 
a dog's head : others to Diana, the goddess of hunting ; and others, that it is the 
faithful dog Maera, which belonged to Icarus, and discovered to his daughter 
Erigone the place of his burial. Others, again, say it is one of Action's hounds 
that devoured their master, after Diana had transformed him into a stag, to pre- 
vent, as she said, his betraying her. 

i; This said, the man began to disappear 
By slow degrees, and ended in a deer. 
Transformed at length, he flies away in haste, 
And wonders why he flies so fast. 
But as by chance, within a neighb'ring brook, 
He saw his branching horns, and alter'd look, 
Wretched Acteeon ! in a doleful tone 
He tried to speak, but only gave a groan; 
And as he wept, within the watery glass, 
He saw the big round drops, with silent pace, 
Run trickling down a savage, hairy face. 
What should he do? or seek his old abodes. 
Or herd among the deer, and skulk in woods 7 
As he thus ponders, he behind him spies 
His opening hounds, and now he hears their cries. 
From shouting men. and horns, and dogs he flies. 
When now the fleetest of the pack that press'd 
Close at his hepls, and sprung before the re^t, 
Had fastened on him, straight another pair 
Hung on his wounded side, and held him there, 
Till all the pack came up. and every hound 
Tore the sad huntsman groveling on the ground."* 

It is most probable, however, that the Egyptians were the inventors of this cor>- 
stellation ; and as it always rises a little before the Dog Star, which, at a particu- 
lar season, they so much dreaded, it is properly represented as a little watchful 
creature, giving notice like a faithful sentinel of the other's approach. 



* It is not difficult to deduce the moral of this fable. The selfishness and caprice of 
human friendship furnish daily illustrations of it. AVhile the good man. the philan- 
thropist, or the public benefactor, is in affluent circumstances, and, with a heart to de- 
vise, has the power to minister blessings to his numerous beneficiaries, his virtues are 
the general theme: but when adverse storms have changed the ability, though they 
could not shake the will of their benefactor, he is straightway pursued, like Actteon, by 
his own bourtds ; and, like Action, he is " torn to the ground" by the fangs that led 
upon his bounty.— L. O.. C. L. 

What name is usually given to the Little Dog ? When does Procyon rise and culmi- 
nate, with respect to the Dog Star ? What name, for this reason, was given to this con- 
stellation > 



MAP HI.] 



MONOCEROS. CAMS MAJOR. 



71 



MONOCEROS. 

The Unicorn. — This is a modern constellation, which 
was made out of the unformed stars of the ancients that lay 
scattered over a large space of the heavens between the two 
Dogs. It extends a considerable distance on each side of 
the equinoctial, and its center is on the same meridian with 
Procyon. 

It contains 31 small stars, of which the seven principal 
ones are of only the 4th magnitude. Three of these are 
situated in the head, 3° or 4° apart, forming a straight line 
N. E. and S. W. about 9° E. of Betelguese in Orion's shoul- 
der, and about the same distance S. of Alhena in the foot of 
the' Twins. 

The remaining stars in this constellation are scattered 
over a large space, and being very small, are unworthy of 
particular notice. 

-History. — The Moxoceros is a species of the Unicorn or Rhinoceros. It is 
about the size of a horse, with one white horn growing out of the middle of its 
forehead. It is said to exist in the wilds of Ethiopia, and to be very formidable. 

Naturalists say that, when pursued by the hunters, it precipitates itself from 
the tops of the highest rocks, and pitches upon its horn, which sustains the whole 
force of its fall, so that it receives no damage thereby. Sparmano "Informs us, 
that the figure of the unicorn, described by some of the ancients, has been found 
delineated on the surface of a rock in Caffraria ; and thence conjectures that 
such' an animal, instead of being fabulous, as some suppose, did once actually 
exist in Africa. Loho affirms that he has seen it. 

The rhinoceros, whicti is akin to it, is found in Bengal. Siam. Cochin China, 
part of China Proper, and the isles of Java and Sumatra. 



CANIS MAJOR. 

The Great Dog. — This interesting constellation is situ- 
ated southward and eastward of Orion, and is universally 
known by the brilliance of its principal star, Sirius, which 
is apparently the largest and brightest in the heavens. It 
glows in the winter heniisphe.e with a luster which is un- 
equaled by any other star in the firmament. 

Its distance from the earth, though computed at 20 millions 
of millions of miies, is supposed to be less than that of any 
other star: a distance, however, so great that a cannon bail, 
which flies at the rate of 19 miles a minute, would be two 
millions of years in passing over the mighty interval ; while 
sound, moving at the rate of 13 miles a minute, would reach 
Sirius in little less than three millions of years. 

What Btare compose the con<tell;«ion Monoreros? How is this constellation situ- 
ate"], and \\ hen i- it on tie merii iaii ? What is the wh<ve number o! it- stars ? What 
is the magnitude of its princip: 1 ones 1 D ■-r-.i'.nj <|.o e i i h • hea i D s ribe the po- 
sition and appearance of Can s .V-jor. Wha! • - ■*> api c inu.ee in the winter? What 
ice t'om the earth computed t>> lie. " d how i it c nr.pa-vd with that of the 
other stars? How Ion.' would r take i ■-■> u <>n-b I] lo p;us ..v r th s distance, la wha 
time would sound -each Sirinj \< tr he ca h 



72 PICTURE OP THE HEAVENS. [FEB. 

It may be shown in the same manner, that a ray of light, which occupies only 
8 minutes and 13 seconds in coming to us from the sun, which is at the rate of 
nearly two hundred thousand miles a second, would be 3 years and 82 days in 
passing through the vast space that lies between Sirius and the earth. Conse- 
quently, were it blotted from the heavens, its light would continue visible to us 
for a period of 3 years and 82 days after it had ceased to be. 

If the nearest stars give such astonishing results, what shad we say of thaw 
which are situated a thousand times as far beyond these, as these are from us 7 

In the remote ages of the world, when every man was his 
own astronomer, the rising and setting of Sirius. or the Dog 
Star, as it is called, was watched with deep and various so- 
licitude. The ancient Thebans, who first cultivated astro- 
nomy in Egypt, determined the length of the year by the 
number of its risings. The Egyptians watched its rising 
with mingled apprehensions of hope and fear ; as it was omi- 
nous to them of agricultural prosperity or blighting drought. 
It foretold to them the rising of the Nile, which they called 
Siris, and admonished them when to sow. The Romans 
were accustomed yearly to sacrifice a dog to Sirius, to render 
him propitious in his influence upon their herds and fields. 
The eastern nations generally believed the rising of Sirius 
would be productive of great heat on the earth. 

Thus Virgil :— 

"Turn steriles exurere Sirius agros : 

Ardebant herbee, etvictum seges aegra negabat " 

1* Parched was the grass, and blighted was the corn : 

Nor 'scape the beasts ; for Sirius, from on high, 
With pestilential heat infects the sky." 

Accordingly, to that season of the year when Sirius rose 
with the sun and seemed to blend its own influence with the 
heat of that luminary, the ancients gave the name of Dog- 
days, (Dies Canicular es .) At that remote period the Dog- 
days commenced on the 4th of August, or four days after 
the summer solstice, and lasted forty days or until the 14th 
of September. At present the Dog-days begin on the 3d of 
July, and continue to the 11th of August, being one day less 
than the ancients reckoned. 

Hence, it is plain that the Dog-days of the moderns have 
no- reference whatever to the rising of Sirius, or any other 
star, because the time of iheir rising is perpetually acceler- 
ated by the precession of the equinoxes: they have reference 
then only to the summer solstice which never changes its 
position in respect to the seasons. 

How long ii light in coming from Sirius to the enrtlv Suppose this star were now 
be bloVedfrom the heavens, how long bfure its twinkling would expire 7 How WW 
die rising of Sirius regarded in the remoie a'-es of the World ? What use was made of 
it by the ancient Thebans? How did the Egyptians regard it, and lor what reason ? 
Whatdid it foretell to them ? What did the Romans offer in sacrifice to Sirius annually 1 
Why? How was it regarded by the eastern nations generally? What season ot the 
ye*r did thu ancients call Dog-days? When did these begin, and how long did they 
last ? A present, when do they begin and end ? Have our Dog-days any reference to 
Vaa Dog Star ? 



MAP. III.] CANIS MAJOR. 73 

The time of Sinus' rising varies with the latitude of the place, and in the same 
latitude, is sensibly changed after a course of years, on account of the precession 
at the equinoxes. This enables us to determine with approximate accuracy, 
the dates of many events of antiquity, which cannot be well determined by other 
records. We do not know, for instance, in what precise period of the world 
ITesiod flourished. Yet he tells us in his Opera et Dies, lib. ii. v. 1S5, that Arcta- 
rus in his time rose heliacally, 60 days after the winter solstice, which then 
was in the 9th degree of Aquarius, or 39^ beyond its present position. Now 
39° : 50j"= 2794 years since the time of Hesiod, which corresponds very nearly 
with history. 

When a star rose at sun-setting, or set at sun rising, it was called the Achroni- 
eal rising or setting. When a planet or star appeared above the horizon just be- 
fore the sun, in the morning, it was called the Heliacal rising of the star ; and 
when it sunk below the horizon immediately aftei the sun, in the evening, it waa 
called the Heliacal setting. According to Ptolemy, stars of theirs; magnitude 
are seen rising and setting when the sun is 12° below the horizon ; stars of the 
2d magnitude require the sun's depression to be 13 a ; stars of the 3d magnitude, 
14°, and so on, allowing one degree for each magnitude. The rising and setting 
of the stars described in this way, since this mode of description often occurs 
in Hesiod, Virgil, Columella, Ovid, Pliny, &c, are called poetical rising and set-' 
ting. They served to mark the times of religious ceremonies, the seasons allotted 
to the several departments of husbandry, and the overflowing of the Nile. 

The student may be perplexed to understand how the 
Dog Star, which he seldom sees till mid-winter, should be 
associated with the most fervid heat of summer. This is 
explained by considering that this star, in summer, is over 
our heads in the daytime, and in the lower hemisphere at 
night. As " thick the floor of heaven is inlaid with patines 
of bright gold," by day, as by night; but on account of the 
superior splendor of the sun, we cannot see them. 

Sirius is situated nearly S. of Alhena, in the feet of the 
Twins, and about as far S. of the equinoctial as Alhena is 
N. of it. It is about 10° E. of the Hare, and 26° S. of Be- 
telguese in Orion, with which it forms a large equilateral 
triangle. It also forms a similar triangle with Phaet in the 
Dove, and Naos in the Ship. These two triangles being 
joined at their vertex in Sirius, present the figure of an enor- 
mous X, called by some, the Egyptian X. Sirius is also 
pointed out by the direction of the Three Stars in the belt 
of Orion. Its distance from them is about 23°. It comes to 
the meridian at 9 o'clock on the 11th of February. 

Mirzam, in the foot of the Dog, is a star of the 2d mag- 
nitude. 5h° W. of Sirius. A little above, and 4° or 5° to the 
left, there are three stars of the 3d and 4th magnitudes, form- 
ing a triangular figure somewhat resembling a dog's head. 



What is meant by the Achronical rising and setting of the stars? What, by their 
Heliacal rising and setting 7 By tohom xoere the terms thus applied, and what toers 
these risings and settings called 1 What did they serve ? Expliiin how it is, that the 
Dog Star, which is seldom seen till mid-winter, should be associated with the most 
fervid heat of summer. Are there as many stars over our head in the daytime as in the 
night? Describe the situation of Sirius. What is ifs position with regard to Betelguese 
and Proryon, and in connection with them what ligue does it form? With what other 
stars does it form a similar triangle? What is the appearance of these two triangles 
taken tosether? How else is Sirius pointed out- Describe the position and magni- 
tude of Alirzam. What sars mak the head of the Dog. 



74 PICTURE OF THE HEAVENS. [MAR. 

The brightest of them, on the left, is called Muliphen. It 
entirely disappeared in 1670, and was not seen again for 
more than 20 years. Since that time it has maintained a 
steady luster. 

Wesen is a star of between the 2d and 3d magnitudes, in 
the back. 11° S. S. E. of Sirius, with which, and Mirzam in 
the paw, it makes an elongated triangle. The two hinder 
feet are marked by Naos and Lambda, stars of the 3d and 
4th magnitudes, situated about 3° apart, and 12° directly S. 
of the forefoot. This constellation contains 31 visible stars, 
including one of the 1st magnitude, four of the 2d, and iwo 
of the 3d ; all of which are easily traced out by the aid of 
the map. 

History.— Manillas, a Latin poet who flourished in the Augustan age, wrote 
an admirable poem, in five books, upon the fixed stars, in which he thus speak* 
of this constellation : — 

<; All others he excels ; no fairer light 
Ascends the skies, none sets so clear and bright." 

But Ettdosia best describes it : — 

" Next shines the Dog with sixty -four distinct ; 

Famed for pre-eminence in envied song, 

Tiieme of Homeric and Virgiltan lays : 

His fierce mouth flames with dreaded Sinus ; 

Three of his stars retire with feeble beams." 
According to some mythologists, this constellation represents one of Orion's 
Rounds, which was placed in the sky, near this celebrated huntsman. Others 
say it received its name in honor of the dog given by Aurora to Cephalus, which 
surpassed in speed all the animals of his species. Cephalus.it is said, attempted 
to prove, this by running him against a fox, which, at that time, was thought to 
be the fleetest of all animals. Alter they had run together a long time without 
either of them obtaining the victory, it is said that Jupiter was so much gratified 
at t lie lleetness of the do?, that he assigned him a place in the heavens. 

But the name and form of this constellation are, no doubt, derived from the 
Egyptians, who carefully watched its rising, and by it judged of the swelling of 
the Nile, which they called Siris, and, in their hieroglyphical manner of writing, 
nince it was as it were the sentinel and watch of the vear, represented it under 
the figure of a dog. They observed that when Sirius 'ecame visible in the east, 
just before the morning: dawn, the overflowing of the Nile immediately followed. 
Thus it warned them, like a faithful dog, to escape from the region of the inun- 
dation. 



CHAPTER V. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE MERIDIAN IN MARCH. 

ARGO NAVIS. 

The ship Argo. — This constellation occupies a large 
space in the southern hemisphere, though but a small part 

Which is the brightest of these, and what remarkable circumstance in its history? 
How has it appeared since \U return ? Describe the situation and magnitude of We- 
gen ? What stars mark the hinder feet? What is the number of visible stars in thi* 
•onstellation ) Describe the constellation Argo Navis 1 



MAP III. J ARGO NAVIS. 75 

of it can be seen in the United States. It is situated S. E. 
of Canis Major, and maybe known by the ..tars in the prow 
and deck of the ship. 

If a straight line joining Betelguese and Sirius. be pro- 
duced 18° to the southeast, it will point out News, a star of 
the 2d magnitude, in the rowlock of the ship. This star is 
in the S. E. corner of the Egyptian X, and of the large 
equilateral triangle made by itself with Sirius and the Dove. 
When on the meridian, it is seen from this latitude about 8° 
above the southern horizon. It comes to the meridian on 
the 3d of March, about half an hour after Procyon, and con- 
tinues visible but a \"e\v hours. 

Gamma, in the middle of the ship, is a star of the 2d mag- 
nitude, about 7° S. of Naos, and just skims above the south- 
ern horizon for a few minutes, and then sinks beneath it. 
The principal star in this constellation is called, after one 
of the pilots, Canopusj it is of the 1st magnitude. 36° nearly 
S. of Sirius. and comes to the meridian 17 minutes after itj 
but having about 53° of S. declination, it cannot be seen in 
the United States. The same is true of Miaplacidus. a star ' 
of the 1st magnitude in the oars of the ship, about 25° E. of 
Canopus, and 61° S. of Alphard, in the heart of Hydra. 

An observer in the northern hemisphere, can see the stars as many degrees 
soudi of the equinoctial in the southern hemisphere, as bis own la'.kude lacks oi 
90°, and no more. 

Markeb. is a star of the 4th magnitude, in the prow of the 
ship, and may be seen from this latitude, 16° S. E. of Sirius, 
and about 10° E. of Wesen. in the back of the Dog. This 
star may be known by its forming a small triangle with two 
others of the same magnitude, situated a little above it, on 
the E.. 3° and 4° apart. 

This constellation contains 64 stars, of which lwo are of 
the 1st magnitude, tour of the 2d, and nine of the 3d. Most 
of these are too low down to be seen in the United States. 

History. — This constellation is intended to perpetuate the memory of the- 
famous ship which carried Jason and his 54 companions to Colchis, when they 
resolved upon the perilous expedition of recovering the 2olden fleece. T\,e de- 
rivat.on of the word Argu has been o:";en disputed. Some derive it from Argos, 
supposing that this was the name of the person who first proposed the expedition, 
and built the ship. Others maintain that it was built at Ar^os. whence its name. 
Cicero calls it Argo, because it carried Grecians, commonly called Argives. 
Diodorus derives the word from «pyos, winch signifies swift. Ptolemy says. 
but not truly, that Hercules built the ship and called it Argo. after a son ot Jason, 
who bore the same name. This ship had fifty oars, and being thus propelled 
must have fallen tar short of the bulk of the smallest *hip craft used by moderns. 

Where is it situated? Point our the situation of Xao«, in the ship? When may it be 
seen in this latitude .' When is i; on the meridian? Describe the position and magni- 
tude of Gamma. What are ;h ; situation and name of t lie principal star in thi< constel- 
lation ? Why can it no; be seen in the United ^ta'es .' I< any other considerate star 
in the shi.. similarly situated 3 Describe Markeb. How may this star be known! 
What I- tiie number ofvi-ilde aturs in this constellation 3 What is the magnitude of its 
prin ipal otK-a .' 



76 PICTURE OF THE HEAVEN?. [itfAR- 

It is even said that the crew were able to carry it on their backs from the Dan- 
ube to the Adriatic. 

According to many authors, she had a beam on her prow, cut in the forest of 
Dodona by Minerva, which had the power of giving oracles to the Argonauts. 
This ship was the first, it is said, that ever ventured on the sea. After the expe- 
dition was finished, and Jason had returned in triumph, he ordered her to b^ 
drawn ashore at the isttimus of Corinth, and consecrated to Neptune, the god of 
the sea. 

Sir Isaac Newton endeavors to settle the period of this expedition at about 30 
years before the destruction of Troy, and 43 years after the death of Solomon. 
Dr. Bryant, however, rejects the history of the Argonautic expedition as a mere 
fiction of the Greeks, and supposes that this group of stars, which the poets de- 
nominate Argo Navis, refers to Noah's ark and the deluge, and that the fable of 
the Argonautic expedition is founded on certain Egyptian traditions that related 
to the preservation of Noah and his family during the flood. 



CANCER 

The Crab is now the fifth constellation and fourth sign 
of the Zodiac. It is situated in the ecliptic, hetween Leo on 
the E. and Gemini on the W. It contains 83 stars, of which 
one is of the 3d, and seven of the 4th magnitude. Some 
place the first-mentioned star in the same class with the other 
seven, and consider none larger than the 4th magnitude. 

Beta is a star of the 3d or 4th magnitude, in the south- 
western claw. 10° N. E. of Procyon, and maybe known from 
the fact that it stands alone, or at least has no star of the 
same magnitude near it. It is midway between Procyon 
and Acubens. 

Acubens, is a star of similar brightness, in the south-eastern 
claw, 10° N. E. of Beta, and nearly in a straight line with it 
and Procyon. An imaginary line drawn from Capella through 
Pollux, will point out Acubens, at the distance of 24° from 
Pollux. It may be otherwise distinguished by its standing 
between two very small stars close by it in the same claw. 

Tegmine, the last in the back, appears to be a small star, 
of between the 5th and 6th magnitudes, 8£° in a northerly 
direction from Beta. It is a treble star, and to be distinctly 
seen, requires very favorable circumstances. Two of them 
are so near together that it requires a telescopic power of 
300 to separate them. 

About 7° north-easterly from Tegmine, is a nebulous clus- 
ter of very minute stars, in the crest of Cancer, sufficiently 
luminous to be seen hy the naked eye. It is situated in a 
triangular position with regard to the head of the Twins and 
the Little Dog. It is about 20° W. of each. It may other- 
wise be discovered by means of two conspicuous stars of 

What is the relative position of Cancer among- the signs and constellations of the 
Zo'iiac ; How is it situated.' What are the number ami magnitude of its etark! 
Where is Beta situated, :tud how may it be known ! Which way from Procyon and 
Acubens? Describe Reubens. What are i's disance and direction from Pollux ? How 
may it be otherwise known? Dcseribe-ifei.'mine. There is a temarkable cluster la 
this consteiluuon— deserve its position^ How may it otherwise b« discovered) 



< 



MAP III.] CANCER. 77 

the 4th magnitude lying one on either side of it, at the dis- 
tance of about 2°, called the northern and southern Aselli. 
By some of the Orientalists, this cluster was denominated 
Praisepe, the Manger, a contrivance which their fancy fitted 
up for the accommodation of the Aselli or Asses ; and it is 
so called by modern astronomers. The appearance of this 
nebula to the unassisted eye, is not unlike the nucleus of a 
comet, .and it was repeatedly mistaken for the comet of 
1832, which, in the month of November, passed in its neigh- 
borhood. 

The southern Asellus, marked Delta, is situated in the 
line of the ecliptic, and, in connection with Wasat and Tejat, 
marks the course of the earth's orbit for a space of 36° from 
the solstitial colure. 

There are several other double and nebulous stars in this 
constellation, most of which are too small to be seen ; and 
indeed, the whole constellation is less remarkable for the 
brilliancy of its stars than any other in the Zodiac. 

The sun arrives at the sign Cancer about the 21st of June, 
but does not reach the constellation until the 23d of July. 

The mean right ascension of Cancer is 126°. It is coni»e- 
quently on the meridian the 3d of March. 

A few degree ' S. of Cancer, and about 17° E. of Procyon. are four stars of the 
i'li magnitude, 3° or 4° apart, which mark the head of Hydra. This constella- 
tion will be described on Map III. 

The beginning of the sign Cancer (not the constellation) is called the Tropic 
of Cancer, and when the sun arrives at this point, it has reached its utmost limit 
of north declination, where it seems to remain stationary a few days before A 
begins to decline again to the south. This stationary attitude of the sun is called 
the summer solstice ; from two Latin words signifying the sun's standing still. 
The distance from the first point of Cancer to the equinoctial, which, at present, 
is 23° 27g', is called the obliquity of the ecliptic. It is a remarkable and well-as- 
certained fact, that this is continually growing less and less. The tropics are 
slowly and steadily approaching the equinoctial, at the rate of about half a second 
every year ; so that the sun does not now come so far north of the equator in 
summer, nor decline so far south in winter, as it must have done at the creation, 
by nearly a degree. 

History.— In the Zodiacs of Esne and Dendera, and in most of the astrologi- 
cal remains of Egypt, a Scara! eeus, or Beetle, is used as the symbol of this sign : 
but in Sir William Jones' Oriental Zodiac, and in some others found in India, we 
meet with the figure of a crab. As the Hindoos, in all probability, derived their 
knowledge of the stars from the Chaldeans, it is supposed that the figure of the 
crab, in this place, is more ancient than the Beetle. 

In some eastern representations of this sign, two animals, like asses, are foun'.' 
in this division of the Zodiac: and as the Chaldaic name for the ass may br 
translated muddiness. it is supposed to allude to the discoloring of the Nile., 
which river was rising when the suu entered Cancer. The Greeks, in copying 
this sign, have placed two asses as the appropriate symbol of it, which still rte- 

What is the name of this cluster? "What is it--? appearance to the naked eye, and for 
wh:it has it been mistaken? How is the star culled Hie southern Asellus situated, 
with respect to the ecliptic? What other stars in this conatClationl At wbattiffie 
does the sun enter the sign Cancer.' At what time the constellation i. Where a ./<■ 
fropic of Cancer situated f When the sun r.arhes //•>>• ,oint, what is said oj its ut 
chnatvm 1 What is tin* stationary attitude oj' t ic sun called ! What is i)i£. obuqr.,:- 
oftfv. ecliptic ? What remarkable fad in respect to thU distance ? Due* tlux affect i 
stability of the tropics • 



78 riCTURE OF THE HEAVENS. [ APRIL. 

main. They explain their reason, however, for adopting this figure, by saying 
that these are the animals that assisted Jupiter in his victory over the giants. 

Dopuis accounts for the origin of the asses in the following words: — Le Cancer, 
r.u sont les etoiles appellees les anes, forme l'impreinte du pavilion d' Issachai 
quo Jacob assimile a l'ane. 

Mythologists give different accounts of the origin of this constellation. The 
prevailing opinion is, that while Hercules was engaged in his famous contest 
with the dreadful Lerneean monster, Juno, envious of the fame of his achieve- 
ments, sent a sea-crab to bite and annoy the hero's feet, but the crab being soon 
dispatched, the goddess to reward its services, placed it among the constella- 
tions. 

"The Scorpion's claws here clasp a wide extent, 
And here the Crab's in lesser clasps are bent." 



CHAPTER VI. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE MERIDIAN IN APRIL. 

LEO. 

The Lion. — This is one of the most brilliant constellations 
in the winter hemisphere, and contains an unusual number 
of very bright stars. It is situated next E. of Cancer, and 
directly S. of Leo Minor and the Great Bear. 

The Hindoo astronomer, Varaha. says, " Certainly the southern solstice was 
once in the middle of Asleha (Leo) ; the northern in the first degree of Dhan- 
is/ita" (Aquarius). S nee that time, the solstitial, as well as the equinoctial 
points, have gone backward on the ecliptic 75°. This divided by 50^", srivea 
5373 years; which carry us back to the year of the world 464. Sir W. Jones 
says, that Varaha lived when the solstices were in the first degrees of Cancer 
and Capricorn ; or about 400 years before the Christian era. 

Leo is the fifth sign, and the sixth constellation of the 
Zodiac. The mean right ascension of this extensive group 
is 150°, or 10 hours. Its center is therefore on the meridian 
the sixth of April. Its western outline, however, comes to 
the meridian on the 18th of March, while its eastern limit 
does not reach it before the 3d of May. 

This constellation contains 95 visible stars, of which one 
is of the 1st magnitude, one of the 2d, six of the 3d, and fif- 
teen of the 4th. 

« One splendid star of highest dignity, 
One of the second class the Lion boasts, 
And justly figures the fierce summer's rage." 

The principal star in this constellation is of the 1st mag- 
nitude, situated in the breast of the animal, and named Re- 
&vlu8. from the illustrious Roman consul of that name. 

What is the general appearance of the constellation Leo? Where is it situated? 
What is :he relative order among the signs ami constellations of the Zodiac 7 What is 
Uw right ascension of Leo, and when is its ccn'er on the meridim ? When do the out- 
lines ot the figure come to the meridian.' What number of vsilile stars does it contain, 
»nd how large are the principal ores ? What is the name of the tirst star in the con- 
stellation, and whence is it derived I 



HAP IV.] LEO. 79 

It is situated almost exactly in the ecliptic, and may be 
readily distinguished on account of its superior brilliancy. It 
is the largest and lowest of a group of five or six bright 
stars which form a figure somewhat resembling a sickle, in 
the neck and shoulder of the Lion. There is a little star of 
the 5th magnitude about 2° S. of it. and one of the 3d mag- 
nitude 5° N. of it, which will serve to point it out. 

Regulus is the brightest star in the constellation. Great 
use is made of it, by nautical men. for determining their 
longitude at sea. Its latitude, or distance from the eclip- 
tic, is less than \° ; but its declination, or distance from the 
equinoctial, is nearly 13° N. ; so that its meridian altitude 
will be just equal to that of the sun on the 19th of August - 
Its right ascension is very nearly 150°. It therefore cul- 
minates about 9 o'clock on the 6th of April. 

When Regulus is on the meridian. Castor and Pollux are seen about 40° N. W. 
of it, and the two stars in the Little Dog are about the same distance in a S. W. 
direction ; with which, and the two former, it makes a large isosceles triangle 
whose vertex is at Regulus. 

The next considerable star is 5° N. of Regulus, marked 
Eta. situated in the collar; it is of between the 3d and 4th 
magnitudes, and with Regulus constitutes the handle of the 
sickle. Those three or four stars of the 3d magnitude, N. 
and W. of Eta. arching round with the neck of the animal, 
describe the blade. 

Al Gieba is a bright star of the 2d magnitude, situated in 
the shoulder, 4° in a N. E. direction from Eta, and may 
be easily distinguished by its being the brightest and mid- 
dle one of the three stars lying in a semicircular form curving 
toward the west; and it is the first in the blade of the 
sickle. 

Adhafera is a star of the 3d magnitude, situated in the 
neck. 4° N. of Al Gieba, and may be known by a very mi- 
nute star just below it. This is the second star in the blade 
of the sickle. 

Ras al Asad, situated before the ear, is a star of the 3d 
or 4th magnitude, 6° W. of Adhafera, and is the third in 
'he blade of the sickle. The next star. Epsilon, of the same 
magnitude, situated in the head, is2£° S. W. of Ras al Asad, 
and a little within the curve of the sickle. About midway 



Describe the situation of Reeulus. What other stars serve to point it out ! What it 
its comparative brightness ? What use is made of it in nautical astronomy J What are 
its latitude and declination? On what day will Repulus culminate at 9 o'clock in the 
evening ? Wfun is it on the meridian, xcith what stars does it form a large triangle, 
and in ichat direction are they from ill What are the name and position of the ne.rt 
considerable star in its vicinity :■ What stars Ibrm the blade of the sickle » Where is 
Al Gieba situated, and how nviy it be distinguished ! What is the position of Adhafera. 
and how muy it be known 7 Describe the situation of Has al Asad. 



80 PICTURE OF THE HEAVENS. [APRIL. 

between these, and a little to the E.. is a very small star 
hardly visible to the naked eye. 

Lamhda, situated in the mouth, is a star of the 4th magni- 
tude, 3^° S.W. of Epsilon, and the last in the sickle's point 
Kappa, situated in the nose, is another star of the same 
magnitude, and about as far from Lambda as Epsilon. 
Epsilon and Kappa are about bh° apart, and form the long- 
est side of a triangle, whose vertex is in Kappa. 

Zozma, situated in the back of the Lion, is a star of the 
3d magnitude, 18° N. E. of Regulus, and midway between 
it and Coma Berenices, a fine cluster of small stars, 18° N. 
E. of Zozma. 

Thela. situated in the thigh, is another star of the 3d mag- 
nitude, 5° directly S. of Zozma, and so nearly on the same 
meridian that it culminates but one minute after it. This 
star makes a right-angled triangle with Zozma on the N. 
and Denebola on the E., the right angle being at Theta. 

Nearly in a straight line with Zozma and Theta, and 
Eouth of them, are three or four smaller stars, 4° or 5° apart, 
which mark one of the legs. 

Denebola. is a bright star of the first magnitude, in the 
brush of the tail, 10° S. E. of Zozma, and may be distin- 
guished by its great brilliancy. It is 5° W. of the equinoc- 
tial colure. and comes to the meridian 1 hour and 41 minutes 
after Regulus, on the 3d of May ; when its meridian altitude 
is the same as the sun's at 12 o'clock the next day. 

When Denebola is on the meridian. Regulus is seen 25° W. of it, and Phad, in 
the square of Ursa Major, bears 39° N. of it. It forms, with these two. a large 
right-angled triangle : the right ansrle being at Denebola. It is so nearly on the 
same meridian with Phad that it culminates only four minutes before it. 

Denebola is 35h° W. of Arcturus, and about the same dis- 
tance N. W. of Spica Virginis. and l'orms, with them, a large 
equilateral triangle on the S. E. It also forms with Arctu- 
rus and Cor Caroli a similar figure, nearly as large on the 
N. E. These two triangles, being joined at their base, con- 
stitute a perfect geometrical figure of the forms of a Rhom- 
bus, called by some, the Diamond of Virgo. 

A line drawn from Denebola throush Resulus. and continued 7° or 8° further 
in the same direction, will point out Xi and O/nicron, of the 3d and 4th magni- 
tudes, situated in the foreclaws, and about 3° apart. 

"What star is next? Describe the position of Lambda. "What are the situation and 
magnitude of Kappa? What is the distance between Epsilon and Kappa? Describe 
the position of Zozma. What are the magnitude an/1 position of Theta t What geo- 
metrical figure may be formed with this star. Zozma and Denebola ? What stars in (hit 
neighborhood murk one of the legs of Leo? De.-cribe Denebola. How far is it from 
the equinoctial colure, and when does it come to the meridian ' When Dtnelola is on 
the meridian, what geometrical figure does it form, in c/nnection with Regulus and 
Phad 1 With what other star is it nearly on the same meridian i What is the position 
of Denebola in regard to Arcturus and Spica Virginis, and what figure dors it form with 
them? With what other stars does Denebola form a similar figure ? What large geo- 
metrical figure is formed by these two triangle* ? Wlial ttars point out tlio.c in ihd 
foreclaws ) 



MAP IV.] LEO. 81 

There are a number of other stars of the 3d and 4th magnitudes in this con- 
stellation, which require no description, as the scholar will easily trace them out 
from the map. The position of Regulus and Denebola are often referred to in 
the geography of the heavens, as they serve to point out other clusters in the 
same neighborhood. 

History. — According to Greek fable, this Lion represents the formidable ani- 
mal which infested the forests of Nemaea. It was slain by Hercules, and placed 
by Jupiter among the stars in commemoration of the dreadful conflict. Some 
writers have applied the story of the twelve labors of Hercules to the progress 
of the sun through the twelve signs of the ecliptic ; and as the combat of that 
celebrated hero w 7 ith the Lion was his first labor, they have placed Leo as the 
first sign. The figure of the Lion was, however, on the Egyptian charts long 
oefore the invention of the fables of Hercules. It would seem, moreover, ac- 
cording to the fable itself, that Hercules, who represented the sun, actually slew 
the Nemsean Lion, because Leo was already a zodiacal sign. 

In hieroglyphica! writing the Lion was an emblem of violence and fury; and 
the representation of this animal in the Zodiac, signified the intense heat occa- 
sioned by the sun when it entered that part of the ecliptic. The Egyptians were 
much annoyed by lions during the heat of summer, as they at that season left 
the desert, and haunted the banks of the Nile, which had then reached its greatest 
elevation. It was therefore natural for their astronomers to place the Lion where 
we find him in the Zodiac. 

The figure of Leo, very much as we now have it, is in all the Indian and Egyp- 
tian Zodiacs. The overflowing of the Nile, which was regularly and anxiously 
expected every year by the Egyptians, took place when the sun was in this sign. 
They therefore paid more attention to it. it is to be presumed, than to any other. 
This was the principal reason, Mr. Green supposes, why Leo stands first in the 
zodiacs of Deudera. 

The circular zodiac, mentioned in our accouuis of Aries, and which adorned 
the ceiling in one of the inner rooms in the famous temple in that city, was 
brought away en masse in 1821, and removed to Paris. On its arrival at the 
Louvre, it was purchased by the king for 150,000 francs, and, after being exhibited 
there for a year, was placed in one of the halls of the library,' where it is now to be 
seen in apparently perfect preservation. This most interesting relic of astrology, 
after being cut aw-.iy fioni the ruins where it was found, is about one foot thick, 
and eight feet square. The rock of which it is composed, is sandstone. On the 
face of this stone appears a large square, inclosing a circle four feet in diame- 
ter, in which are arranged, in an irregular spiral line, the zodiacal coustellations, 
commencing with the sL r n Leo. On each side of this spiral line are placed a 
great variety of figures. These are supposed to represent other constellations, 
though they bear no analogy, in form, to those which we now have. Many of 
these figures are accompanied with hieroglyphics, which probably express tneir 
names. The commentator of Champollion, from whom we have derived many 
interesting facts in relation to them, has furnished merely a general history of 
their origin and purpose, but does not add particulars. Copies of these drawings 
and character have been exhibited in this country, and the wonderful conclu- 
sions that have been drawn from them have excited much astonishment. 

Compared with our present planispheres, or with stellar phenomena, it abounds 
with contradictory and irrelevant matter. So far from proving what was strenu- 
ously maintained by infidel writers, soon after its discovery, that the Greeks 
took from it the model of their zodiac, which they have transmitted to us, it 
seems to demonstrate directly the reverse. The twelve signs, it is true, are 
there, but they are not in their proper places. Cancer is between Leo and the 
pole ; Virgo bears no proportion to the rest ; some of the signs are placed double ; 
they are all out of the ecliptic, and by no means occupy those regular and equal 
portions of space which Egyptian astronomers are said to have exactly measured 
by means of their clepsydra. 

The figures, without what may be termed the zodiacal circle, could never have 
included the same stars in the heavens which are now circumscribed by the 
figures of the constellations. Professor Green is of opinion, that the small 
apartment in the ruins of Dendera. which was mysteriously ceiled with this 
zodiac, was used for the purposes of judicial astrology, and that the sculptured 
figures upon it wore employed in horoscopical predictions, and in that casting of 
nativities for which the Egyptians were so famous. 



Why U the potition ofRegulw and Dembola often referred tot 



82 PICTURE OF THE HEAVENS. [ APRIL. 

In the Hebrew Zodiac, Leo is assigned to Judah.on whose standard, according 
to all traditions, a Lion is painted. This is clearly intimated in numerous passa- 
ges of the Hebrew writings : Ex.— " Judah is a Lion's whelp ; he stooped down, 
he couched as a Lion, and as an old Lion; who shall rouse him up 1" Gen. 
xlix. 9. "The Lion of the tribe of Judah hath prevailed." Rev. v. 5. 



LEO MINOR. 

The Little Lion. — This constellation was formed by 
Hevelius, out of the Stellce informes, or unformed stars of 
the ancients, which lay scattered between the Zodiacal con- 
stellation Leo on the S., and Ursa Major on the N. Its mean 
right ascension is the same with that of Regulus. and it 
comes to the meridian at the same time on the 6th of April. 

The modem constellations, or those which have been added to our celestial 
maps since the adoption of the Greek notation, in 1603, are referred to by the 
letters of the English alphabet, instead of the Greek. This is the case in regard 
to Leo Minor, and all other constellations whose origin is subsequent to that 
period. 

Leo Minor contains 53 stars, including only one of the 3d 
magnitude, and 5 of the 4th. The principal star is situated 
in the body of the animal, 13° N. of Gamma Leonis,* in a 
straight line with Phad, and may be known by a group of 
smaller stars, a little above it on the N. W. 

It forms an equilateral triangle with Gamma and Delta Leonis, the vertex being 
in Leo Minor. This star is marked with the letter /., in modern catalogues, and 
being the principal representative of the constellation, is itself sometimes called 
the Little Lion : 8° E. of this star (the Little Lion) are two stars of the 4th mag- 
nitude, in the last paw of Ursa Major and about 10° N. W. of it, ale two other 
6tars of the 3d magnitude, in the first hind paw. 

'• The Smaller Lion now succeeds ; a cohort 
Of fifty stars attend his steps ; 
And three, to sight unarm'd, invisible." 



SEXTANS. 

The Sextant, called also Urania's Sextant^ is a mod 
ern constellation that Hevelius made out of the unformed 
stars of the ancients, which lay scattered between the Lion 
on the N.j and Hydra on the S. 

It contains 41 very small stars, including only one as large 

* Leonis is (he genitive or possessive case of Leo, and Gamma Leonis means the 
Gamma of Leo Thus also the principal star in Aries is marked Alpha Arietis, mean- 
ing the Alpha of Aries, ttc. 

f Urania was one of the muses, and daughter of Jupiter and Mnemosyne. She pre- 
sided over astronomy. She was represented as a young virgin, dressed in an azure- 
colored robe, crowned with stars, holding a robe in her hands, and having many math- 
ematical instruments about her. 

What is the origin of Leo Minor, and how is it situated ? AVhat is its mean right as- 
cension ? When is it on the meridian? What are the number and magnitude of its 
stars ? What is the po-ition of the principal sfarin this constellation, and ho\r may it 
be known ! What figure does it form with some, other stars I What letter represents 
this star, and tahat else is it called ? What nebula do ice find, in this constellation? 
What are the origin and position of the Sextant ? How many star* does it contain ? 



MAP IV.] HTDKA AND THE CUP. 83 

as the 4th magnitude. This is situated very near the equi- 
noctial, 13° S. of Regulus, and comes to the meridian about 
the same time on the 6th of April. The other stars in this 
constellation are too small to engage attention. A few of the 
largest of them may be traced out from the map. 

History. — A sextant, in mathematics*, is the sixth part of a circle, or an arch 
comprehending 60 degrees. But the term is more particularly used to denote 
an astronomical instrument well known to mariners. Its use is the same as that 
of the quadrant ; namely, to measure the angular distance, and take the altitude 
of the sun, moon, planets, and fixed stars. It is indispensable to the mariner in 
finding the latitude and longitude at sea, and should be in the hands of every 
surveyor and practical engineer. It may serve- the purpose of a theodolite, in 
measm-ing inaccessible heights and distances. It may gratify the youns pupil to 
know, that by means of such an instrument, well adjusted, and with a clear eye 
and a steady hand, he could readily tell, within a few hundred yards, how far 
north or south of the equator he was, and that from any quarter of the world, 
known or unknown. This constellation is so called, on account of a supposed 
resemblance to this instrument. 



HYDRA AND THE CUP. 

Hydra, the Water Serpent, is an extensive constella- 
tion, winding from E. to W. in a serpentine direction, over a 
space of more than 100 degrees in length. It lies south of 
Cancer, Leo and Virgo, and reaches almost from Canis 
Minor to Libra. It contains sixty stars, including one of the 
2d magnitude, three of the 3d, and twelve of the 4th. 

Alphard, or Cor Hydra, in the heart, is a lone star of the 
2d magnitude, 23° S. S. W. of Regulus, and comes to the 
meridian at the same time with Lambda, in the point of the 
sickle, about 20 minutes before 9 o'clock on the 1st of April. 
There is no other considerable star near it, for which it can 
be mistaken. An imaginary line drawn from Gamma Leonis 
through Regulus, will point out Cor Hydrae, at the distance 
of 23°. 

The head of Hydra may be distinguished by means of four 
stars of the 4th magnitude, 2h° and 4° apart, situated (5° S. 
of Acubens, and forming a rhomboidal figure. The three 
upper stars in this cluster form a small arch, and may be 
known by two very small stars just below the middle one, 
making with it a very small triangle. The three western 
stars in the head also make a beautiful little triangle. The 
eastern star in this group, marked Zela, is about 6° directly 
S. of Acubens, and culminates at the same time. 

When Alphard is on the meridian. Alkes, of the 4th mag- 
nitude, situated in the bottom of the Cup, may be seen 24° 

What is the position of the largest one J Describe the situation and extent of the 

Constellation Hydra. What are the number and magnitude of its star*.' 0> M -ribe the 

. nd magnitude of Aluhard. What a.e die distance and direction of Cor Hy- 

a '■ .omnia Leonis? How may the head of Hydra be distinguished ; How may 

ee uuper stars in this chis-cr be known? Which stars form a beautiful h'tk: 

triangle ? How is Alkes situated, and when may it be seen ? 



84 PICTURE OF THE HEAVENS. [APRIL. 

S. E. of it, and is distinguished by its forming an equilateral 
triangle with Beta and Gamma, stars of the same magni- 
tude. 6° S. and E. of it. Alkes is common both to Hydra and 
the Cup. Beta, on the S., is in Hydra, and Gamma, on the 
N. E., is near the middle of the Cup. A line drawn from 
Zozma, through Theta Leonis, and continued 381° directly 
S. will reach Beta ; it is therefore on the same meridian, and 
will culminate at the same time on the 23d of April. 

The Cup itself, called also the Crater, may be easily dis- 
tinguished by means of six stars of the 4th magnitude, form- 
ing a beautiful crescent, or semicircle, opening to the W. 
The center of this group is about 15° below the equinoctial, 
and directly S. of "the hinder feet of Leo. The crescent 
form of the stars in the Cup is so striking and well defined, 
when the moon is absent, that no other description is neces- 
sary to point them out. Its center comes to the meridian 
about two hours after Alphard. on the same evening ; and 
consequently, it culminates at 9 o'clock, one month aftei 
Alphard does. The remainder of the stars in this constel- 
lation may be easily traced by aid of the map. 

When the head of Hydra is on the meridian, its other ex- 
tremity is many degrees below the horizon, so that its whole 
length cannot be traced out in the heavens until its center, 
or the Cup, is on the meridian. 

" Near the equator rolls 

The sparkling Hydra, proudly eminent 

To drink the Galaxy's refulgent sea; 

Nearly a fourth of the encircling curve 

Which girds the ecliptic, his vast folds involve ; 

Yet ten the number of his stars diffused 

O'er the long track of his enormous spires : 

Chief beams his heart, sure of the second rank, 

But emulous to gain the first." — Eudosia. 
History.— The astrologers of the east, in dividing the celestial hosts into vari- 
ous compartments, assigned a popular and allegorical meanins to each. Thus 
the sign Leo, which passes the meridian about midnight, when the sun is in 
Pisces, was called the House of the Lions, Leo being the domicil of Sol. 

The introduction of two serpents into the constellations of the ancients, had its 
origin, it is supposed, in the circumstances that the polar one represented the 
oblique course of the stars, while the Hydra, or Great Snake, in the southern 
hemisphere, symbolized the moon's course; hence the Nodes are called the 
Dragon's head and tail to this day. 

The hydra was a terrible monster, which, according to mycologists, infested 
the neishborhood of the lake Lcrna, in the Peloponnesus. It had a hundred 
heads, according to Diodorus ; fifty, accordins to Simonides; and nine, accorcU 
ing to the more commonly received opinion of Apollodorus, Hyjiinus. and others. 
As soon as one of these heads was cut off, two immediately grew up if the wound 
was not stopped by fire. 

If Alkes be situated in the Cup, whv is it also included in Hydra ? How are the other 
two stars that make a triangle with Alke< .situated? How is B«ta situated with respect 
to Zozma and Theta Leonis i When is Beta on the meridian? How may the Cup be 
distinguished ? How is the center of this group situated with respect to Leo and the 
equinoctial ? What single circumstance is sufficient to designate the stars in the Cup? 
When is it on the meiidian? When the hasd ef Hydra is on the meiidian where ia the 
other extremity of the ronst^llafion ? 



MAP VI.] URSA MAJOR. 35 

" Art thou proportion'd to the hydra's length, 
Who by his wounds received augmented strength f 
He raised a hundred hissing- heads in air, 
When one I lopp'd, up sprang a dreadful pair." 
To destroy this dreadful monster, was one of the labors of Hercules, and 
this he easily effected with the assistance of Iolaus, who applied a burning iron 
to the wounds as soon as one head was cut off. While Hercules was destroying 
the hydra, Juno, jealous of his dory, sent a sea-crab to bite his foot. This new 
enemy was soon dispatched ; and Juno was unable to succeed in her attempts 
to lessen the fame of Hercules. The conqueror dipped his arrows in the gall of 
the hydra, which ever after rendered the wounds inflicted with them incurable 
and mortal. 

This fable of the many-headed hydra may be understood to mean nothing more 
than that the marshes of Lerna were inferred with amultitude of serpents," which 
seemed to multiply as fast as they were destroyed. 



CHAPTER VII. 



DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE ON 
THE MERIDIAN IN MAY. 

URSA MAJOR. 

The Great Bear. — This great constellation is situated 
between Ursa Minor on the north, and Leo Minor on the 
south. It is one of the most noted and conspicuous in the 
northern hemisphere. It has been an object of universal ob- 
servation in all ages of the world. The priests of Belus and 
the Magi of Persiathe shepherds, of Chaldea. and the Phoe- 
nician navigators, seem to have been equally struck with its 
peculiar outlines. And it is somewhat remarkable, that a re- 
mote nation of American Aborigines, the Iroquois, and the 
earliest Arabs of Asia, should have given to the very same 
constellation the name of " Great Bear," when there had 
probably never been any communication between them ; and 
when the name itself is so perfectly arbitrary, there being no 
resemblance whatever to a bear, or to any other animal. 

It is readily distinguished from all others by means of a 
remarkable cluster of seven bright stars, forming what is fa- 
miliarly termed the Dipper, or Ladle. In some parts of Eng- 
land it is called "Charles' Wain," or wagon, from its fancied 
resemblance to a wagon drawn by three horses in a line. 
Others call it the Plough. The cluster, however, is more fre- 
quently put for the whole constellation, and called simply the 
Great Bear. But we see no reason to reject the very ap- 

How is Ursa Major situated ? How has it always been regarded i What people seem 
to have been peculiarly struck with its splendor? What TemarkapLe circumstance re- 
specting its name ? Is there any resemblance between the outlines of tins constellation 
and the figure of a bear? By what is this constellation readily distinguished from all 
others? By what other names is the Dipper called' What is this cluster more fre- 
quently called ? 



86 



PICTURE OF THE HEAVENS. 



[MAY 



propriate appellation of the shepherds, for the resemblance 
is certainly in favor of the Dipper; the four stars in the 
square forming the bowl, and the other three the handle. 

When the Dipper is on the meridian, above the pole, the 
bottom lies toward us, with the handle on the right. 

Benetnasch is a bright star of the 2d magnitude, and is 
the first in the handle. The second, or middle star in the 
handle is Mizar, 7° distant from Benetnasch. It may be 
known by means of a very minute star almost touching it, 
called Alcor, which appears to be double when seen through 
a telescope, and of a silver white. The third star in the han- 
dle is called Alioth, and is about 4£° W. of Mizar. Alioth 
is very nearly opposite Shedir in Cassiopeia, and at an equal 
distance from the pole. Benetnasch, Mizar, and Alioth con- 
stitute the handle, while the next four in the square form 
the bowl of the Dipper. 

Five and a half degrees W. of Alioth is the first star in 
the top of the Dipper, at the junction of the handle, called 
Megrez ; it is the smallest and middle one of the cluster, 
and is used in various observations both on sea and land for 
important purposes.* At the distance of 4£° S. W. of Me- 
grez is Phad, the first star in that part of the bottom which 
is next the handle. 

The stars in this cluster are so well known, and may be so easily described 
without reference to their relative bearings, that they would rather confuse than 
assist the student, were they given with ever so much accuracy. The .-everal 
bearings for this cluster were taken when Megrez was on the meridian, ami will 
not apply at any other time, though their respective distances will remain the 
same. 

At the distance of 8° W. of Phad, is the westernmost star 
in the bottom of the Dipper, called Merak. The bright star 
5° N. of it, toward the pole, is called Dubhe ; but these two, 
Merak and Dubhe. are, by common consent, called the 
Pointers, because they always point toward the pole; for, 
let the line which joins them be continued in the same di- 
rection 23f° farther, it will just reach the north pole. 

The names, positions, and relative distances of the stars in 
this cluster should be well remembered, as they will be Ire- 



* When Megrez and Caph have the same altitude, and are seen in the same horizon- 
tal line east and west, the polar star is then at its greatest elongation from the true 
pole of the heavens ; and this is the proper lime for an observer to take its angle of ele- 
vation, in order to determine the latitude, and its azimuth or angle of declination, in 
order to determine the magnetic variation. 



What, on the whole, is an approt riate appellation for it, and why? Describe 'he i o 
Ntion of the Dipper when on the merUi :n. Describe the josi'ion of Ben hiasch. 
What is the next s'arin the Dipi-e r , .Mid how tnrtv i' be known ' What is th 
third star in the Dipper? Whar stars fo-m the bowl .-nd handle of the I'ii , 
scribe the position ami use of Megrez. Wh.-.t star i- situaed n.wt to .A eirezi I) scribe 
the position ot .Merak and Dubhe. What are the it' Mars called, and why ' 



MAP VI.] URSA MAJOR. 87 

quently adverted to. The distance of Dubhe, or the Pointer 
nearest to the north pole, is 281°. The distance between the 
two upper stars in the Dipper is 10° ; between the two lower 
ones is 8°; the distance from the brim to the bottom next the 
handle, is 4|° ; between Megrez and Alioth, is 5h° ; between 
Alioth and Mizar,4|° ; and between Mizar and Benetnasch,7°. 

The reason why it is important to have these distances clearly settled in the 
mind is. that these stars, being always in view, and more familiar than any other, 
the student will never fail to have a standard measure before him, which the eye 
can easily make use of in determining the distances between other stars. 

The position of Megrez in Ursa Major, and of Caph in 
Cassiopeia, is somewhat remarkable. They are both in the 
equinoctial colure, almost exactly opposite each other, and 
equally distant from the pole. Caph is in the colure, which 
passes through the vernal equinox, and Megrez is in that 
which passes through the autumnal equinox. The latter 
passes the meridian at 9 o'clock, on the 10th of May, and the 
former just six months afterward, at the same hour, on the 
10th of November. 

Psi, in the left leg of Ursa Major, is a star of the 4th mag- 
nitude, in a line with Megrez and Phad, distant from the 
latter 12i°. A little out of the same line, 3° farther, is 
another star of the 4th magnitude, marked Epsilon, which 
may be distinguished from Psi, from its forming a straight 
line with the two Pointers. 

The right forepaw, and the two hinder ones, each about 
15° from the other, are severally distinguished by two stars 
of the 4th magnitude, between 1° and 2° apart. These three 
duplicate stars are nearly in a right line, 20° S. of, and in a 
direction nearly parallel with Phad and Dubhe, and are the 
only stars in this constellation that ever set in this latitude. 

There are a few other stars of equal brightness with those 
just described, but amidst the more splendid and interesting 
group with which they are clustered, they seldom engage 
our observation. 

The whole number of visible stars in this constellation is 
87 ; of which five are of the 2d, two of the 3d, and about 
twice as many of the 4th magnitude. 

History.— Ursa Major is said to be Calisto, or Helice, daughter of Lycaon, 



What is the distance of Dubhe from the north pole ? Mention the relative distances 
between the other star.s in this group). Why is it important to have, the relative distan- 
ces of these stars from each other well settled in the. mind ? What is there remarkable 
in the position ol Megrez, and Ca] h in Cassiopeia? When do they pass the meridian ? 
Describe the position of Psi. Where is L'.psilon situated, and how may it be distin- 
guished * How are die pawsofthe Bear distinguished ! What is the situation of these 
Stars with respect to Phad and iJnbho .' What are the only stars in this constellation 
that ever set in this latitude? What is the whole number ol" visible stars in tins con- 
stellation, and how many of each magnitude.' 



88 PICTURE OF THE HEAVENS. [MAT. 

king of Arcadia. She was an attendant of Diana,* and mother of Areas, by Jo- 
piter, who placed her among the constellations, after the jealousy of Juno had 
changed her inio a bear. 

'• This said, her hand within her hair she wound. 

Swung her to earth, and dragg'd her on the ground ; 

The prostrate wretch lifts up her hand in prayer; 

Her arms grow shaggy, and deforrjrd with hair, 

Her nails are sharpen'd into pointed claws, 

Her hands bear half her weight, and turn to paws; 

Her lips, that once could tempt a god, begin 

To grow distorted in an ugly grin ; 

And lest the supplicating brute mijiht reach 

The ears of Jove, she was deprived of speech. 

How did she fear to lodge in woods alone, 
And haunt the fields and meadows, once her own ! 
How often would the deep-mouth'd dogs pursue, 
Whilst from her hounds the frighted hunters flew."— Ovid's Met. 
Some suppose that her son Areas, otherwise called Bootes, was changed into 
Ursa Minor, or the Little Bear. It is well known, that the ancients represented 
both these constellations under the figure ofawaL'on drawn by a team of horses; 
hence the appellation of Charles' Wain, or wagon. This is alluded to in the 
Phenomena of Aratus, a Greek poem, from which St. Paul quotes in his address 
to the Athenians: — 

•• The one call'd Helix.t soon as day retires, 
Observed with ease lights up his radiant fires : 

* Diana was the goddess of hunting, and the patroness of modesty and chastity ;— 
" The huntress Dian, 
Fair, silver-shafred queen, forever chaste, 

set at naught 

The frivolous bolt of Cupid; gods and men 
Fear her stern frown, and she was queen o rh' woods."— Milton. 
The most famous of her temples was that of Ephcsus. near Smyrna, in Asia, which 
was one of the seven wonders of the world. It is related in the Acts of the Apostles, 
that " Demetrius, a silversmith, who made silver shrines f.r Diana," endeavored to ex- 
cite opposition to the Christian religion, because "this Paul had persuaded much 
people that they be no gods which are made with hands," and " that the temple of the 
great goddess Diana should be despi.-ed, and her magnificence should be destroyed, 
whom all Asia and the world worshipeth. And when they heard these sayings they 
were full of wrath, and cried out, saying. Great is D ana of the Ephesians! And thus 
they continued shouting for the space of two hoars.'' Are! again, "When the town 
clerk had appeased the people, he said. Ye men o: " EpIiL-sus, what man is there that 
knoweth not how that: the city of the Ephesians is a Wirshiper of the great goddess 
Diana, and of the image which fell down from Jupiter?" 

The " image which fell down from Jupiter," doubtless alludes to the fable that Juno 
'.ast her out of heaven, and that Neptune, in piry of her desolate condition, raised the 
Bland of Delos. from the jEgean sea, for her biith ami habitation ; ;or it was in this 
aland that the twins, Apollo and Diana, were born. Diana is therefore sometimes 
.'.ailed Delia, from the name of the island that gave her birth, she was represented 
under the figare of a very beautiful virgin, in a hunting d es . a head taller than any of 
her attendant nymphs, with a bow in her hand, a quiver susr.t nded across her shoal- 
lie's, and her forehead ornamented w th a silver crescent 'which Jews might kiss and 
infidels adore." The inhabitants ofTaurica sacrificed upon her altars all the stranger! 
that were shipwrecked upon their coast. The Lacedemonians yearly offered her hu- 
man victims till the age of Lycurgus, who changed this barbarous custom of immo- 
lation to flagellation. The Athenians generally offered her goats, while others offered 
white kids and ewes. 

" Haste the sacrifice ; 
Seven bullocks yet unyoked for Phoebus choose. 
And for Diana, seven unspotted ewes." — Virgil. 
Who does not bow with grateful veneration at that Christian intrepidity of St. Paul, 
who risked his life in exposing the delusion and idolatry of the worshipers of the god- 
dess Diana ? 

It is a remnrkable circumstance, that the temple of Diana was burnt to the ground 
the very day on which Alexander the great was born ! 

. i Cahsto was a native of the city of Helice, in Achaia, a district near the bar of Co- 
rinth ; hence the Greater Bear is sometimes called Helice : — 
" Night on the earth pour'd darkness ; on the sea, 
The watchful sailor, to Orion's star 
And Helice, turn'd heedful."— Apo lion ins. 



MAP IV.] COMA BERENICES. S9 

The other, smaller, and with feebler beams, 
In a less circle drives its lazy teams ; 
But more adapted for the sailor's guide, 
Whene'er, by night, he tempts the briny tide." 
In fne Egyptian planispheres of remote antiquity, these two constellations are 
represented by the figures of bears, instead of wagons; and the Greeks, who 
derived most of their astronomical symbols from the Egyptians, though they 
usually altered them to emblems of their own history or superstition, have never- 
theless, retained the original form of the two bears. It is said by Aratus, that the 
Phenician navigators made use of Ursa Minor in directing their voyages:— 

" Observing this, Phenicians plough the main :" 
while the Greeks confined their observations to Ursa Major. 

Some imagine that the ancient Egyptians arranged the stars near the north 
pole within the outlines of a bear, because the polar regions are the haunts of 
this animal, and also because it makes neither extensive journeys nor rapid 
marches. 

At what period men began to sail by the stars, or who were the first people 
that did so, is not clear ; but the honor is usually given to the Phenicians. That 
it was practiced by the Greeks, as early as the time of the Trojan war, that is, 
about 1200 years B. C, we learn from Homer; for he says of Ulysses, when 
sailing on his raft, that 

"Placed at the helm he sate, and mark'd the skies, 
Nor closed in sleep his ever watchful eyes." 
It is rational to suppose that the stars were first used as a guide to travelers 
by land, for we can scarcely imagine that men would venture themselves upon 
the sea by night, before they had first learned some safe and sure method of 
directing their course by land. And we find, according to Diodorus S. cuius, that 
travelers in the sandy plains of Arabia were accustomed to direct their course 
by the Bears. 

That people traveled in these vast deserts at night by observing the stars, is 
directly proved by this passage of the Koran : — '• God has given you the stars to 
be guides in the dark, both by land and by sea." 



COMA BERENICES. 

Berenice's Hair. — This is a beautiful cluster of small 
Btars, situated about 5° E. of the equinoctial colure, and mid- 
way between Cor Caroli on the north-east, and Denebola on 
the south-west. If a straight line be drawn from Benetnasch 
through Cor Caroli, and produced to Denebola. it will pass 
through it. 

The principal stars are of between the 4th and 5th magni- 
tudes. According to Flamsted, there are thirteen of the 4th 
magnitude, and according to others there are seven; but the 
student will find agreeably to his map, that there is apparently 
but one star in this group, entitled to that rank, and this is 
situated about 7° S. E. of the main cluster. 

Although it is not easy to mistake this group for any other 
in the same region of the skies, yet the stars which compose 
it are all so small as to be rarely distinguished in the full 
presence of the moon. The confused luster of this assem- 

Describe the appearance and situation of Coma Berenices. What are the magnitudes 
of the principal stars in this cluster? What are they, according to Flamsted and others? 
How many stars of the 4th magnitude will the student find on the map ? Is it easy to 
mistake this group, and is it visible in presence of the moon? 

8* 



90 PICTURE OF THE HEAVENS. L MAY. 

blage of small stars somewhat resembles that of the Milky- 
Way. It contains, besides the stars already alluded to, a 
number of nebulee. 

The whole number of stars in this constellation is 43; its 
mean right ascension is 185°. It consequently is on the me- 
ridian the 13th of May. 

" Now behold 

The glittering maze of Berenice's Hair ; 
Forty the stars ; but such as seem to kiss 
Thejlotcing- tresses with a lambent fire, 
Four to the telescope alone are seen." 
History —Berenice was of royal descent, and a lady of great beauty, who 
married Ptolemy Soter, or Evergetes, one of the kings of Egypt, her own brother, 
whom she loved with much tenderness. When he was going on a dangerous 
expedition against the Assyrians, she vowed»to dedicate her hair to the goddess 
of beauty, if he returned in safety. Sometime after the victorious return of her 
husband, Evenretes, the locks, which, agreeably to her oath, she had deposited in 
the temple of Venus, disappeared. The king expressed great regret at tne loss of 
what he so much prized ; whereupon Conon, his astronomer, publicly reported 
that Jupiter had taken away the queen's locks from the temple, and placed them 
among the stars. 

" There Berenice's locks first rose so bright. 
The heavens bespangling with disheveled light.'' 
Conon, being sent for by the kins, pointed out this constellation, saying, 
" There behold the locks of the queen." This group being among the unformed 
stars until that time, and not known as a constellation, the king was satisfied 
with the declaration of the astronomer, and the queen became reconciled to the 
partiality of the gods. 

Callimachus, a historian and poet, who flourished long before the Christian 
era, has these lines as translated by Tytler :— 

"Immortal Conon, blest with skill divine, 
Amid the sacred skies behold me shine : 
E'en me, the beauteous hair, that lately shed 
Refulgent beams from Berenice's head ; 
The lock she fondly vowed with lifted arms, 
Imploring all the powers to save from harms 
Her dearer lord, when from his bride he flew, 
To wreak stern vengeance on the Assyrian crew." 



CORVUS. 

The Crow. — This small constellation is situated on the 
eastern part of Hydra, 15° E. of the Cup, and is on the same 
meridian with Coma Berenices, but as far S. of the equinoc- 
tial as Coma Berenices is N. of it. It therefore culminates 
at the same time, on the 12th of May. It contains nine visi- 
ble stars, including three of the 3d magnitude and two of 
the 4th. 

This constellation is readily distinguished by means ol 
three stars of the 3d magnitude and one of the 4th, forming 
a trapezium or irregular square, the two upper ones being 
about 3|° apart, and the two lower ones 6° apart. 

What does its luster resemble ? What is the number of stars in this constellation, 
and when is it on the meridian 1 Where is the Crow situated ' When is it on the me 
ridian? What are the number and magnitude of its stars i How is it readily distin- 
guished ? 



MAP IV.] CORVUS. 91 

The brightest of the two upper stars, on the left, is called 
Algorab, and is situated in the E. wing of the Crow; it has 
nearly the same declination S. that the Dog Star has. and is 
on the meridian about the 13th of May. It is 2H° E. of 
Alkes in the Cup, 14£° S. W. of Spica Virginis, a brilliant 
star of the 1st magnitude to be described in the next 
chapter. 

Beta, on the back of Hydra and in the foot of the Crow, is 
a star of the 3d magnitude, nearly 7° S. of Algorab. It is the 
brightest of the two lower stars, and on the left. The right- 
hand lower one is a star of the 4th magnitude, situated in the 
neck, marked Epsilon, about 6° W. of Beta, and may be 
known by a star of the same magnitude situated 2° below it, 
in the eye, and called Al Chiba. Epsilon is 21§° S. of the 
vernal equinox, and if a meridian should be drawn from the 
pole through Megrez, and produced to Epsilon Corvi, it 
would mark the equinoctial colure. 

Gamma, in the W. wing, is a star of the 3d magnitude, 
3|° W. of Algorab, and is ihe upper right-hand one in the 
square. It is but 1° E. of the equinoctial colure. 

10° E. of Beta is a star of the 3d magnitude, in the tail of 
Hydra, marked Gamma; these two, with Algorab, form 
nearly a right-angled triangle, the right angle being at Beta. 

History. — The Crow, it is said, was once of the purest white, but was changed 
for tale-bearing to its present color. A fit punishment for such a fault ' 
'• The raven once in snowy plumes was drest, 
White as the whitest dove's unsullied breast, 
Fair as the guardian of the capitol, 
Soft as the Swan ; a large and lovely fowl ; 
His tongue, his prating tongue, had changed him quite. 
To sooty blackness from the purest white." 
According to Greek fable, the Crow was made a constellation by Apollo. This 
god being jealous of Coronis, (whom he tenderly loved,) the daughter of Phle- 
gyas and mother of ^Esculapius, sent a crow to watch her" behavior; the bird 
perceived her criminal partiality for Ischys the Thessalian. and immediately 
acquainted Apollo with her conduct, which so fired his indignation that he lodged 
an arrow in her breast, and killed her instantly. 

" The god was wroth ; the color left his look, 
The wreath his head, the harp his hand forsook ; 
The silver bow and feathered shafts he took, 
And lodged an arrow in the tender breast, 
That had so often to his own been presL" 
To reward the crow, he placed her among the constellations. 
Others say that this constellation takes its name from the daughter of Coro- 
naeus, king of Phocis, who was transformed into a crow by Minerva, to rescue 
the maid from the pursuit of Neptune. The following, from an eminent Latin 

[>oet of the Augustan age, is her own account of the metamorph»sis as trans- 
ated into English verse by Mr. Addison : — 

u For as my arms I lifted to the skies, 
I saw black feathers from my fingers rise : 

Describe the position of Algorab. How does its declination compare with that of 
Sinus ) What are its distance and direction from Alkes and Spica Virginia ) Describe 
the situatiou of Beta. Describe the situation of the right-hand lower star. What is 
the distance of Epsilon from the vernal equinox, and how may the equinoctial colur* 
be traced out by it ? What are the magnitude and position of Gamma? Of Beta' 



92 PICTURE OF THE HEAVENS. [.MAT. 

I strove to fling my garment on the ground ; 

My garment turned to plumes, and girt me round : 

My hands to beat my naked bosom try ; 

Nor naked bosom now nor hands had I : 

Lightly I tripp'd, nor weary as before 

Sunk in the sand, but skimm'd along the shore ; 

Till, rising on my wings, I was preferr'd 

To be the chaste'Minerva's virgin bird." 



VIRGO. 

The Virgin. — This is the sixth sign, and seventh constel- 
lation in the ecliptic. It is situated next east of Leo, and 
about midway between Coma Berenices on the N. and Cor- 
vus on the S. It occupies a considerable space in the hea- 
vens, and contains, according to Flamsted, one hundred and 
ten stars, including one of the 1st, six of the 3d. and ten of 
the 4th magnitudes. Its mean declination is 5° N., and its 
mean right ascension is 195°. Its center is therefore on the 
meridian about the 23d of May. 

The sun enters the sign Virgo, on the 23d of August, but does not enter the 
constellation before the 15th of September. When the sun is iu this sign, the 
earth is in Pisces ; and vice versa. 

Spica Virginis, in the ear of corn* which the virgin holds 
in her left hand, is the most brilliant star in this constellation, 
and situated nearly 15° E. N. E. of Algorab in the Crow, 
about 35° S. E. of Denebola, and nearly as far S. S. W. 
of Arcturus — three very brilliant stars of similar magnitude 
that form a large equilateral triangle, pointing to the S. Arc- 
turus and Denebola are also the base of a similar triangle on 
the north, terminating in Cor Caroli, which, joined to the 
former, constitutes the Diamond of Virgo. The length of 
this figure, from Cor Caroli on the north to Spica Virginia 
on the south, is 50°. Its breadth, or shorter diameter, ex- 
tending from Arcturus on the east to Denebola on the west, 
is 35£°. Spica may otherwise be known by its solitary splen- 
dor, there being no visible star near it except one of the 4th 
magnitude, situated about 1° below it, on the left. 

The position of this star in the heavens, has been deter- 
mined with great exactness for the benefit of navigators. It 

* In the Egyptian Zodiac, Isis, whose phce was supplied by Virgo, was represented 
with three ears of corn in her hand. According to the Egyptian mythology, Ism was 
■aid to have dropped a sheaf of corn, as she fled fiom Typhon, who, ss lie continued 
to pursue her, scattered it over the heavens. The Chinese call the Zodiac the yellow 
road, as resembling a path over which the ripened ears of corn are scattered. 

What is the relative position of Virgo among the signs and constellations of the eclip- 
tic? How is it situated ? How many stars does it contain, and how large are the prin- 
cipal ones ? What are its mean declination and risht ascension ? When is the center 
of the constellation on the meridian ? Describe the principal star in Virgo. What are 
the distance and direction of Virgo from Algorab, Denel>ola and Arcturus? What are 
the magnitude and appearance of these three stars, and what figure do they form? 
How may Spica be otherwise distinguished ? Why has iU position been determictl 
with great exactness i 



MAP. IV. j VIRGO. 93 

is one of the stars from which the moon's distance is taken 
for determining the longitude at sea. Its situation is highly- 
favorable for this purpose, as it lies within the moon's path, 
and little more than 2° below the earth's orbit. 

Its right ascension being 199°, it will come to our meridian 
at 9 o'clock about the 28th of May, in that point of the heav- 
ens where the sun is at noon about the 20th of October. 

Vindemiatrix. is a star of the 3d magnitude, in the right arm, or northern 
wing of Virgo, and is situated nearly in a stra'ght line with, and midway between 
Coma Berenices and Spica Virginis. It is 19£° S. W. of Arcturus, and'about tha 
same distance S. E. of Coma Berenices, and" forms with these two a large tri- 
angle, pointing to the south. It bears also 1S°S. S. E. of Denebola, and comes to 
the meridian about 23 minutes before Spica Virginis. 

Zeia. is a star of the 3d magnitude IU° N. of Spica, and very near the equi- 
nocruil. Gamma, situated near the left "side, is also a star of the 3d magnitude, 
and very near the equinoctial. It is 13 3 due west of Zeta. with which and Spica 
it forms'a handsome triangle. Eta. is a star of the 3d magnitude, in the southern 
wing, 5 ; ' W. of Gamma, and but 2*° E. of the autumnal equinox. 

Beta, called also Zavijava, is a" star of the 3d magnitude, in the shoulder of 
the wing. ?j° W. of Era, with which and Gamma it forms a line near the Earth's 
orbit, and parallel to it. Beta. Eta, Gamma and Spica. form the lower and longer 
side of a large spherical triangle whose vertex is in Beta. The other stars in this 
figure may be easily traced by means of the map. About 13 = E. of Spica. there 
are two stars of The 4th magnitude, 3° apart, which mark the foot of Virgo. 
These two stars are on nearly the same meridian with Arcturus, and culminate 
nearly at the same time. The lower one, marked Lambda', is on the south, and 
but 8 b W. of the principal star in Libra. Several other stars of the 3d magnitude 
lie scattered about in this constellation, and may be traced out by the map. 
" Her lovely tresses glow with starry light ; 

Stars ornament the bracelet on her hand ; 

Her vest in ample fold, glitters with stars : 

Beneath her snowy feet they shine ; her eyes 

Lighten, all glorious, with the heavenly rays, 

Baljirst the star which crowns the golden sheaf." 

History. — The famous zodiac of Dendera. as we have already noticed, com- 
mences with the sign Leo : but another zodiac, discovered among the ruins at 
Esne, in Egypt, commences with Virgo : and from this circumstance, some 
have argued, that the regul ir precession of the equinoxes established a date to 
this at leist 2000 years older than <hat at Dendera. The discoveries of Cham- 
puliion, however, "render it probable that this ancient relic of astrology at Esne 
was erected during the reign of the Emperor Claudius, and consequently did not 
precede the one at Dendera more than fourteen years. 

Of this, however, we may be certain : the autumnal equinox now corresponds 
with the first degree of Virgo : and, consequently, if we find a zodiac in which 
the summer solstice was placed where the autumnal equinox now is. that zodiac 
carres us back 90° on the ecliptic ; this divided by the annual precession 501", 
must fix the da!e at about 6450 years ago. This computation, according to the 
chronology of the Sicred writings, carries us back to the earliest ages of the hu- 
man species on earth, and proves, at least, that astronomy was among the first 
studies of mankind. The most rational way of accounting for this zodiac, says 
Jamieson. is to ascribe it to the family of Noah; or perhaps to the patriarch him- 
self, who constructed it for the benefit of those who should live after the deluge, 
and who preserved it as a monument to perpetuate the actual state of the hea- 
vens immediately subsequent to the creation. 

Fable represents the ancient Egyptiaus as believing that the yearly and regu- 
lar inundations of the Nile proceeded from the abundant tears which Isis shed 

Whv is its situation favorable for tnkingr the moon's distance ? When does it pass our 
meridian 1 Describe the situation of Vindemiatrix. Describe the figure which it frms 
With nt er sta>s in the same neighborhood. What are its distance and bearing from 
Denebma^ Describe Zeta. Describe Gamma. Describe the position of Eta. Describe 
the position of Beta. What geometrical figure may be formed ofliic stars in this neigh- 
lorhood? 



94 PICTURE OF THE HEAVEN'S. [MAY. 

for the loss of Osiris, whom Typhon had basely murdered. By confounding the 
simple allegory of the learned with the mythological creed of the vulgar, the his- 
torical account furnished us respecting Isis. becomes perplexed and unintelligible. 
Perhaps with the following key we may unlock the mystery : — The suu in Leo, 
was adored as the god Osiris; in Virjjo, it was worshiped as his sister Isis; at 
its passage into Scorpio, the terrible reign of Typhon commenced. Columella 
fixes the transit of the sun into Scorpio, on the 13th of the calends of November ; 
and this period nearly corresponds with that in which Osiris was feigned to have 
been slain by Typhon, and the death of Orion was to have been occasioned by 
the sting of a scorpion. When Scorpio begins to rise, Orion sets ; when Scorpio 
comes to the meridian, Leo besins to set :— Typhon then reigns, Osiris is slain, 
and his sister follows him to the tomb weeping. The traditions allot the si^ r u 
Virgo to Naphthali, whose standard had for its symbol a tree " bearing goodly 
branches." 

Thus mythology, in describing the physical state of the world, invented a sym- 
bolical language which personified inanimate objects ; and the priests reduced 
the whole of their noblest science to fables, which the people believed as true his- 
tories representing the moral condition of mankind during the first ages of civil 
government. 

According to the ancient poets, this constellation represents the Virgin Astraea, 
the goddess of justice, who lived upon the earth dnringthe golden age; but being 
offended at the wickedness and impiety of mankind during the brazen and iron 
ages of the world, she returned to heaven, and was placed among the constella- 
tions of the zodiac, with a pair of scales (Libra) in one hand and a sword in the 
other. 

Hesiod, who flourished nearly a thousand years before the birth of our Saviour, 
and later writers, mention four ages of the world; the golden, the silver, the 
brazen, and the iron age. In the beginning of things, say tiiey, all men were 
happy, and all men were good ; the earth brought forth her fruits without the 
labor of man: and cares, and wants, wars and diseases, were unknown. But 
this happy state of things did not last long. To the golden aire, the silver age 
succeeded; to the silver, the brazen; and to the brazen, the iron. Perpetual 
spring no longer reigned; men continually quarreled with each other; crime 
succeeded to crime ; and blasphemy and murder stained the history of every 
day. In the golden age, the gods did not disdain to mix familiarly with the sons 
of men. The innocence, the integrity and brotherly love which they found 
among us, were a pleasing spectacle even to superior natures ; but as mankind 
degenerated, one god after another deserted their late beloved haunts; Astraea 
lingered the last ; but finding the earth steeped in human gore, she herself flew 
away to the celestial regions. 

" Victa jacet pietas ; et virgo caede madentes 
Ultima ccelestum terras Astraea reiiquit." 
Met. Lib. i. v. 149. 
" Faith flees, and piety in exile mourns ; 
And justice here oppress'd, to heaven returns." 

Some, however, maintain, that Erigone was changed into the constellation 
Virgo. The death of her father Icarus, an Athenian, who perished by the hands 
of some peasants, whom he had intoxicated with wine, caused a fit of despair, in 
which Erigone hung herself; and she w T as afterward, as it is said, placed among 
the sisns of the zodiac. She was directed by her faithful dog Maera to the place 
where her father was slain. The first bough on which she hung herself break- 
ing, she sought a stronger, in order to effect her purpose. 
"Thus once in Marathon's impervious wood, 
Erigone beside her father stood, 
When hastening to discharge her pious vows, 
She loos'd the knot, and cull' d the strongest boughs." 
Lewis' Statius, B. xi. 



ASTERION ET CHARA ; VEL CANES VENAT1CI. 

The Greyhounds. — This modern constellation, embracing 
two in one. was made by Hevelius out of the unformed stars 

What ia the origin of the constellation called the Greyhounds 7 



MAP IV.] BOOTES. 95 

of the ancients which were scattered between Bootes on the 
east, and Ursa Major on the west, and between the handle 
of trie Dipper on the north, and Coma Berenices on the south. 

These Hounds are represented on the celestial sphere as 
being in pursuit of the Great Bear, which Bootes is hunting 
round the pole of heaven, while he holds in his hand the leash 
by which they are fastened together. The northern one is 
called Asterion, and the southern one, Chara. 

The stars in this group are considerably scattered, and are 
principally of the 5th and 6th magnitudes ; of the twenty-five 
stars which it contains, there is but one sufficiently large to 
engage our attention. Cor Caroli, or Charles'' Heart, so 
named by Sir Charles Scarborough, in memory of King 
Charles the First, is a star of the 3d magnitude, in the neck 
of Chara the Southern Hound. 

When on the meridian, Cor Caroli is 17i° directly S. of Alioth, the third star 
in the handle of the Dipper, and is so nearly on the same meridian that it culmi- 
nates only one minute and a half after it. This occurs on the 20th of May. 

A line drawn from Cor Caroli through Alioth will lead to the N. polar star. 
This star may also be readily distinguished by its being in a straight line with, 
and midway between Benetnasch, the first star in the handle of the Dipper, and 
Coma Berenices ; and also by the fact that when Cor Caroli is on the meridian, 
Denebola bears 23° S. W., and Arcturus 26° S. E. of it, forming with these two 
stars a very large trianirle, whose vertex is at the north ; it is also at the northern 
extremity of the large Diamond already described. 

The remaining stars in this constellation are too small and too much scattered 
to excite our interest 



CHAPTER VIII. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE MERIDIAN IN JUNE. 

BOOTES.* 

The Bear-Dr ver is represented by the figure of a hunts- 
man in a running posture, grasping a club in his right hand, 
and holding up in his left the leash of his two greyhounds, 
Asterion and Chara. with which he seems to be pursuing the 
Great Bear round the pole of the heavens. He is thence 
called Arctophylax, or the " Bear-Driver." 



1 Pronounced Eo-o'-tes. 



How are the Greyhounds represented^ By what names are they distinguished? 
the magnitudes of the stars which compose this group, nnd how are they sit- 
uated with re?pect to each other? Describe the principal star. Witen on the meridian 
what is its situation toith regard to Alioth.] How is Cor Caroli situated with respect 
lliip may this star be othericise readily distinguished 1 What large 
geometrical Jisrw t does u form with two other bright stars in its vicinity] How ia 
the constellation Bootes represented ? Why ie Bootes called tht» Bear Driver I 



96 PICTURE OF THE HEAVENS. [JUNE. 

This constellation is situated between Corona Borealis on 
the east, and Cor Caroli, or the Greyhounds, on the west. It 
eontains fifty-four stars, including one of the 1st magnitude, 
seven of the 3d, and ten of the 4th. Its mean declination is 
20° N., and its mean right ascension is 212°; its center is 
therefore on the meridian the 9lh of June. 

Bootes may be easily distinguished by the position and 
splendor of its principal star. Arcturus, which shines with a 
reddish luster, very much resembling that of the planet Mars. 

Arcturus is a star of the 1st magnitude, situated near the 
left knee, 26° S. E. of Cor Caroli and Coma Berenices, with 
which it forms an elongated triangle, whose vertex is at Arc- 
turus. It is 35|° E. of Denebola, and nearly as far N. of 
Spica Virginis, and forms with these two, as has already 
been observed, a large equilateral triangle. It also makes, 
with Cor Caroli and Denebola, a large triangle whose ver- 
tex is in Cor Caroli. 

A great variety of geometrical figures may be formed of the stars in this brigl't 
region of the ak'ies. For example ; Cor Caroli on the N., anil Spica Virginis on 
the S ., constitute the extreme points of a very large figure in the shape of a dia- 
mond ; while Denebola on the W. and Arcturus on the E., limit the mean diam 
eter at the other points. 

Arcturus is supposed by some to be nearer the earth than 
any other star in the northern hemisphere. 

Five or six degrees S. W. of Arcturus are three stars of the 3d and 4th magni- 
tudes, lying in a cur%-ed line, about 2° apart, and a little below the left knee of 
Bootes; and about 7° E. of Arcturus are three or four other stars of similar mag- 
nitude, situated in the other leg, making a larger curve N. and S. 

Mirac, in the girdle, is a star of the 3d magnitude, 10° N. N. E. of Arcturus, 
and about 11£ Q W. of Alphacca, a star in the Northern Crown. &>'?ginus, in the 
west shoulder, is a star of the 3d magnitude, nearly 20° E. of Cor Caroli, and 
about the same distance N. of Arcturus, and forms with these two, a right-angled 
triangle, the right angle being at Seginus. The same star forms a right-angled 
triangle with Cor Caroli and Alioth, in Ursa Major, the right angle being al Cor 
Caroli. 

Alkaturops, situated in the top of the club, is a star of the 4th magnitude, about 
10>° in an easterly direction from Seginus, which lies in the left shoulder ; and 
about 4£° S- of Alkaturops is another star of the 4th magnitude, in the slub near 
the east shoulder, marked Delta. Delta is about 9° distant from Mirac, and 7£° 
from Alphacca, and forms, with these two, a regular triangle. 

Nekkur is a star of the 3d magnitude, situated in the head, and is about 6 3 N. 
E. of Seginus, and 5° W. of Alkaturops ; it forms, with Delta and Seginus, nearly 
a right angled triangle, the right angle being at Nekkar. 

These are the principal stars in this constellation, except the three stars of 
the 4th magnitude situated in the right hand. These stars may be known by 
two of them being close together, and about 5° beyond Benetnasch, the first star 

How is this constellation situated ? How many stars does it contain ? How large 
are the principal one3 ? What is its mean right ascension ? What is its mean declina- 
tion ? When is its cen f e: on the meridian .< How is it easily distinguished from the 
surrounding constellations? Describe Arcturus. What is its situation with re.-pect to 
Denebo'a and Spica Virsdnis? How is it situated with respect to Cor Caroli anil Dene- 
bola.' What rtmarkab.c configuration in tnis part of the sky] What is the distance 
of Arcturus from ihe earth, compared with that of the other stars in the northern hem- 
isphere ? Wra: stars five or six degree* souiiL-ice.it of Arcturus i What stars in the 
other leg Describe ttie star Mirac. Describe Seginus. With what other stars does 
Seginus form a ri?ih'-a>igled triangle! Describe the position of Alkaturops. Describe 
the position of Delta. Describe Xekkar. 



MAP IV.J BOOTES. 97 

in the handle of the Dipper. About 6° E. of Benetnasch is another star of the 
4th magnitude, situated in the arm, which forms, with Benetnasch and the three 
m the hand, an equilateral triangle. 

The three stars in the left hand of Bootes, the first in the handle of the Dipper, 
Cor Caroli, Coma Berenices, an I Denebola, are all situated nearly in the same 
right line, running from nortn-east to south-west. 

- Bootes follows with redundant light ; 

Fifty four stars he boasts ; one guards the Bear, 

Thence call'd Arcturus, of resplendent front, 

The pride of the first order : eight are veil'd, 

Invisible to the unaided eye." 

Manilids thus speaks of this constellation : — 

u And next Bootes comes, whose order'd beams 
Present a figure driving of his teams. 
Below his girdle, near his knees, he bears 
The bright\4rc/w?-us, fairest of the stars." 

Arcturus is mentioned by name in that beautiful passage 
in Job, already referred to. where the Almighty answers " out 
of the whirlwind," and says: — 

11 Canst thou the sky's benevolence restrain, 

And cause the Pleiades to shine in vainl 

Or. when Orion sparkles from his sphere, 

Thaw the cold seasons and unbind the year! 

Bid Mazzaroth his station know, 

And teach the bright Arcturus where to glow V 

Young's Paraphrase. 
History. — The ancient Greeks called this constellation Lycaon — a name de- 
rived from Xvkos, which signifies a wolf The Hebrews called it Caleb Anubach, 
the " Barking Dog ;" while the Latins, among other names, called it Canis. If 
we go back to the time when Taurus opened the year, and when Virgo was the 
fifth of the zodiacal signs, we shall find that brilliant star Arcturus. so remarka- 
ble for its red and fiery appearance, corresponding with a period of the year as 
remarkable for its heat. Pythagoras, who introduced the true system of the 
universe into Greece, received it from OZnuphis, a priest of On. in Egypt. And 
this college of the priesthood was the noblest of the east, in cultivating the studies 
of philosophy and astronomy. Among the high honors which Pharaoh con- 
ferred on Joseph, he very wisely gave him in marriage -a daughter of the priest 
of On." The supposed era of the book of Job, in which Arcturus is repeatedly 
mentioned, is 1513 B. C. 

Bootes is supposed by some to be Icarus, the father of Erigone, who was killed 
by shepherds for intoxicating them. Others maintain that it is Erichthonius, the 
inventor of chariots. According to Grecian fable, as well as later authorities, 
Bootes was the son of Jupiter and Calisto, and named Areas. Ovid relates, that 
Juno, being incensed at Jupiter for his partiality to Calisto, changed her into a 
bear, and that her son Areas, who became a famous hunter, one day roused a 
bear in the chase, and not knowing that it was his mother, was about to kill her 
when Jupiter snatched them both up to heaven and placed them among the con- 
stellations. Met. b. ii. v 496-503. 

'' But now her son had fifteen summers told, 

Fierce at the chase, and in the forest bold ; 

When as he beat the woods in quest of prey, 

He chanced to rouse his mother where she lay- 

She knew her son. and kept him in her sight, 

And fondly gazed : the boy was in a fright, 

And aim'd a pointed arrow at her breast ; 

And would have slain his mother in the beast ; 

But Jove forbad, and suatch'd them through the air 

In whirlwinds up to heaven, and fix'd 'enfthere ; 

Dtscribe the ihret stars in the Itft hand of Bootrs. What stars in this neighborhood 
form a long line through the tuavens'l Where U Arcturus mentioned in tha Scrip- 
ture* ! 



9S 



PICTURE OF THE HEAVENS. 



[JUNK 



Where the new constellations nightly rise, 
And add a luster to the northern skies." 

Garth's Translation. 
Lccan, in his Pharsalia, says, 

"That Brutus, on the busy times intent, 
To virtuous Cato's humble dwelling went 
'Twas when the solemn dead of nig: it came on, 
When bright Calislo, icith her shining son. 
Now half that circle round the pole had run." 
This constellation is called Bootes, says Cicero, (Nat. Deo. Lib. ii. 42,) from a. 
Greek word signifying a wagoner, or ploughman ; and sometimes Arctophylax 
from two Greeks words signifying bear-keeper or bear-driver. 
" Arctophylax, vulgo qui dicitur esse Bootes. 
Quod quasi temone adjunctum prae se quatit Arctum." 
The stars in this region of the skies seem to have attracted the admiration of 
almost all the eminent writers of antiquity. Claudian observes, that 
" Bootes with his wain the north unfolds ; 
The southern gate Orion holds." 
And Aratus,* who flourished nearly 800 years before Claudian, says, 
" Behind, and seeming to urge on the Bear, 
Arctophylax, on earth Bootes named, 
Sheds o'er the Arctic car his silver light." 



CENTAURUS. 

The Centaur. — This fabulous monster is represented by 



* This is the poet whom St. Paul refers to when he tells the Athenians, Acts xvir 
28, that " some of their own poets have said," " Ton yap xai yevos cufitp : For we 
are also his offspring." These words are the beginning of the 5ih line of the " Pheno- 
mena" of Aratus, a celebrated Greek poem written in thd reign of Ptolemv 1 hila- 
delphus, two thousand one hundred years ago. and afterward tram fated into Latin verse 
by Cicero. Aratus was a poet of St Paul's own country. The apostle bonows again 
from the same poet, both in his Epistle to the Galatians, and to Titus, 'lhe subject of 
the poem was grand and interesting: hence we find it referred to in the wntii 
Clement, St. Jerome, St. Chrysostom, CEcumenius, and others. As this poem de- 
scribes the nature and motions of the stars, and the origin of the constellations, and is, 
moreover. one of lhe oldest compositions extant upon this in ere-ting su!>jt ct. the au- 
thor lias taken some pains to procure a Polyglot eo-y fi uu tscrinamj. together with the 
datronotnican of Manilius, and some other works of similar antiquity, that nothing 
should be wanting on his part which could impart an interest to the study of the con- 
stellations, or illustrate the iiequent allusions to them which we meet with in the 
Scriptures. 

_ Dr. Doddridge says of the above quotation, that ,: these words are well known to lie 
found in Aratus, a poet of Paul's own country, who lived almost 300 years before the 
apostle's time; and that the same words, with the alteration of only one letter, are to 
be found in the Hymn of C/eanthts, to Jupiter, the Supreme God; which is, beyond 
comparison, the purest and finest piece of natural religion, of its length, which I know 
in the whole world of Pagan antiquity ; and which, .-o far as I can recollect, contains 
nothing unworthy of a Christian, or. I had almost said, of an inspired pen. 'I be apo»- 
tle might perhaps refer to Cle.antles, as well as to his countryman Aratus " 

Many of the elements a.ul fables of heathen mythology are so blended with the in- 
spired writings, that they must needs be studied, more o less, in order to have a more 
proper understanding of numerous passages both in the Old and New Testament 

The great apostie of the Gentiles, in utteiinghis inspired sentiments, and in 
his epistles, often refers to, and sometimes quotes verbatim from the distinguished 
writers who preceded him. 

Thus, in 1 Cor. xv. S3, we have " Mri irAavasde • ' QOlioovgiv rjOri \pr,ad' 
ofjiiAiat natal.' Be not deceived; evil communications corrupt good rfl 
which is a literal quotation by the apostle f om the Thais of Menander, an inventor of 
Greek comedy, and a celebrated A 

the apostle wrote hisepistle to the Corinthians. Thus Paul adopts the sentiment of thfl 
comedian, and it becomes hallowed by " the divinity that s tried within him 
tullian remarks, that "in quoting this, the apo tie hath sanctified thej oet's sentiment," 



How is the Centaur represented? 



MAP IV. J LUPUS. 99 

the figure of a man terminating in the body of a horse, hold- 
ing a wolf at arm's length in one hand, while -he transfixes 
its body with a spear in the other. 

Although this constellation occupies a large space in the 
southern hemisphere, yet it is so low down that the main part 
of it cannot be seen in our latitude. It is situated south of 
Spica Virginis, with a mean declination of 50°. It contains 
thirty-five stars, including two of the 1st magnitude, one of 
the 2d, and six of the 3d ; the brightest of which are not 
visible in the United States. 

Theta. is a star of between the 2d and 3d magnitude, in the east shoulder, and 
may be seen from this latitude, during the month of June, being about 27° S. by 
E. from Spica Virginis, and 12° or 13° above the southern horizon. It is easily 
recognized in a clear evening, from the circumstance that there is no other star 
of similar brightness in the same region, for which it can be mistaken. It is so 
nearly on the same meridian with Arcturus that it culminates but ten minutes 
before it. 

Iota is a star of between the 4th and 5ih magnitude, in the west shoulder, 9|° 
W. of Theta. It is about 26° almost directly south of Spica Virginis, and is on 
the meridian nearly at the same time. 

Mu and Nu are stars of the 4th masnitude, in the breast, very near together, 
and form a regular triangle with the two stars in the shoulders. 

A few decrees north of the two stars in the shoulders, are four small stars in 
the head. The relative position of the stars in the head and shoulders is very 
similar to that of the stars in the head and shoulders of Orion. 

History. — Centaurs, in mythology, were a kind of fabulous monsters, half men 
and half horses. This fable is. however, differently interpreted ; some suppose 
the Centaurs to have been a body of shepherds and herdsmen, rich in cattle, who 
inhabited the mountains of Arcadia, and to whom is attributed the invention of 
pastoral poetry. But Plutarch and Pliny are of opinion that such monsters have 
really existed. Others say, that under the reign of Ixion, king of Thessaly, a 
herd of bulls ran mad, and ravaged the whole country, rendering the mountains 
inaccessible; and that some young men, who had found the art of taming and 
mounting horses, undertook to expel these noxious animals, which they pursued 
on horseback, and thence obtained the appellation of Centaurs. 

This success rendering them insolent, they insulted the Lapithee, a people of 
Thessaly; and because, when attacked, they tied with great rapidity, it'was sup- 
posed that they were half horses and half men; men on horses "being at that 
period a very uncommon sight, and the two appearing, especially at a distance, 
to constitute but one animal. So the Spanish calvary at first seemed to the as- 
tonished Mexicans, who imagined the horse and his rider, like the Centaurs of 
the ancients, to be some monstrous animal of a terrible form. 

The Centaurs, in reality, were a tribe of Lapilha?, who resided near Mount 
Pelion, and first invented the art of breaking horses, as intimated bv Virgil. 
" The Lapithaj to chariots add the state 
Of bits and bridles : taught the steed to bound 
To turn the ring, and trace the mazy ground ; 
To stop, to fly, the rules of war to know ; 
To obey the rider, and to dare the foe.'* 



LUPUS. 

The Wolf. — This constellation is situated next east of 
the Centaur, and south of Libra; and is so low down in the 

What is the situation of thi.s constellation? What are the number and magnitude of 
its stars ' Describe the situation of Theta. IIoic is it easily recognized in a dear eve- 
ning) What is its distance from the meridian of Arcturus 7 Describe the star in tilt 
west slumidcr. Desa ibt the stars in tite breast. Wnere is the Wolf situated .' 



100 PICTURE OF THE HEAVENS. [JUNE. 

southern hemisphere, that only a few stars in the group are 
visible to us. 

It contains twenty-four stars, including three of the 3d 
magnitude, and as many of the 4th; the brightest of which, 
when on the meridian, may be seen in a clear evening, just 
above the southern horizon. Their particular situation, how- 
ever, will be better traced out by reference to the map than 
by written directions. 

The most favorable time for observing this constellation 
is toward the latter end of June. 

History. — This constellation, according to fable, is Lycaon, king of Arcadia, 
who lived about 3.600 years ago. and was changed into a wolf by Jupiter, because 
he offered human victims on the altars of the god Pan. Some attribute this 
metamorphosis to another cause. The sins of mankind, as they relate, had be- 
come so enormous, that Jupiter visited the earth to punish its "wickedness and 
impiety. He came to Arcadia, where he was announced as a god. and the peo- 
ple began to pay proper adoration to his divinity. Lycaon. however, who used 
to sacrifice all strangers to his wanton cruelty, laughed at the pious prayers of 
his subjects: and to try the diviniry of the god, served up human flesh on his 
table. This impiety so offended Jupiter, that he immediately destroyed the 
house of Lycaon, and changed him into a wolf. 

"Of these he murders one ; he boils the flesh, 

And lays the mangled morsels in a dish ; 

Some part he roasts ; then serves it up. so dress'd, 

And bids me welcome to his human feast. 

Moved with disdain, the table I o'erturn'd, 

And with avenging flames the palace burn'd. 

The tyrant in a fright for shelter gains 

The neighboring fields, and scours along the plains: 

Howling he fled, and fain he would have spoke, 

But human voice his brutal tongue forsook. 

His mantle, now his hide, with rugged hairs. 

Cleaves to his back : a famish'd face he bears ; 

His arms descend, his shoulders sink away 

To multiply his legs for chase of prey ; 

He grows a wolf."— Ovid. Met. B. i 



i 



LIBRA. 

The Balance. — This is the seventh sign, and eighth con- 
stellation, from the vernal equinox, and is situated in the 
Zodiac, next east of Virgo. 

The sun enters this sign, at the autumnal equinox, on the 
23d of September; but does not reach the constellation be- 
fore the 27th of October. 

Virgo was the goddess of justice, and Libra, the scales, 
which she is usually represented as holding in her left hand, 
are the appropriate emblem of her office. When the sun en- 
ters the sign Libra, the days and nights are equal all over 

How many stars does it contain ? Under what circumstances may the brightest of 
them be seen? How may the stars in this group be most conveniently traced out? 
When is the most favorable time for observing this constellation > How is Libra sit- 
uated among the constellations of the Zodiac? At what season of the year docs the 
eun enter Libra ? Who was Virgo, and what was the emblem of her office ! What is 
the relative length of the days and nights when the sun enters Libra? 



MAP IV.] LIBRA. 101 

the world, and seem to observe a kind of equilibrium, like a 
balance. 

When, however, it is said that the vernal and autumnal 
equinoxes are in Aries and Libra, and the tropics in Cancer 
and Capricorn, it must be remembered that the signs Aries 
and Libra, Cancer and Capricorn, and not the constellations 
of these names, are meant; for the equinoxes are now in the 
constellations Pisces and Virgo, and the tropics in Gemini 
and Sagittarius; each constellation having- gone forward 
one sign in the ecliptic. 

About 22 centuries ago, the constellation Libra coincided 
with the sign Libra; but having advanced 30° or more in 
the ecliptic, it is now in the sign Scorpio, and the constella- 
tion Scorpio is in the sign Sagittarius, and so on. 

While Aries is now advanced a whole sign above the 
equinoctial point into north declination, Libra has descended 
as far below it into south declination. 

Libra contains fifty-one stars, including two of the 2d mag- 
nitude, two of the 3d. and twelve of the 4th. Its mean decli- 
nation is S° south, and its mean right ascension 226°. Its 
center is therefore on the meridian about the 22d of June. 

It may be known by means of its four principal stars, form- 
ing a quadrilateral figure, lying north-east and south-west, 
and having its upper and lower corners nearly in a line run- 
ning north and south. The two stars which form the N. E. 
side of the square, are situated about 7° apart, and distin- 
guish the Northern Scale. The two stars which form the 
S. W. side of the square, are situated about 6° apart, and 
distinguish the Southern Scale. 

Zubeneschamali. in the Southern Scale, about 21° E. of Spica, and S° E. of 
Lambda Virginis. is a star of the 2d magnitude, and is situated very near the 
ecliptic, about 42|° E. of the autumnal equinox. The distance from this star 
down to Theta Ceutauri is about 23°, with which, and Spica Virginis, it forms a 
lame triangle, on the right. 

Zubenelgemabi, the uppermost star in the Northern Scale, is also of the 2d 
magnitude, 9h° above Zubeneschamali, toward the north-east, and it comes to 
the meridian'about twenty-six minutes after it, on the 23d of June. Zubenelge- 
mabi is the northernmost of the four bright stars in this figure, and is exactly 
opposite the lower one, which is 11° south of it. 

Zubenhakrabi is a star of the 3d magnitude in the Northern Scale, 7° S. E. of 
Zubenelgemabi, and nearly opposite to Zubeneschamali, at the distance of 11° on 
the east. Ttiese two make the diagonal of the square east and west. 

Iota is a star of the 4th magnitude, and constitutes the southernmost corner of 

When it is said that the vernal and autumnal equinoxes are m Aries and Libra, and 
the tropics in Cancer and Capricorn, what is meant ? In what constellations, then, are 
the equinoxes and the tropics situated > When did the constellation of Libra coincide 
with the sign of that name/ In what sign is the constellation Libra now situated/ 
What are the number and magnitude of the stars in Libra? What are its right ascen- 
sion and declination '■ When is its center on the meridian ? How may this constella- 
tion be known J What figure do the three upper stars in this G>ure form ! What stars 
distinguish the Northern Scale.' What the Southern ? Describe Zubeneschamali. 
With irha: other star* dot s it form a targe triangle ? Describe the principal star in the 
northern Scale. Describe the position of Zubenhalcrabi. Describe Die position of lota, 

9* 



102 PICTURE OF THE HEAVENS. [JUNE. 

the square. It is about 6° S E. of Zubeneschamali,and 11° S- of Zubenelgemabi, 
with which it forms the other diagonal north and south. 

Zebenelgubi, is a star of the 3d magnitude, situated below the Southern Scale, 
at the distance of 6° from Iota, and marks the southern limit of the Zodiac. It is 
situated in a right line with, and nearly midway between Spica Virginis avid Beta 
Scorpionis ; and comes to the meridian nearly at the same moment with Nekkar, 
in the head of Bootes. 

The remaining stars in this constellation are too small to engage attention. 

The scholar, in tracing out this constellation in the heavens,' will perceive that 
Lambda and Mu, which lie in the feet of Virgo on the west, form, with Zubenes- 
chamali and Zubenelgemabi, almost as handsome and perfect a figure, as the 
other two stars in the Balance do on the east. 

History.— The Libra of the Zodiac, says Maurice, in his Indian Antiquities, is 
perpetually seen upon all the hieroglyphics of Egypt ; which is at once an argu- 
ment of the great antiquity of this asterism. and of the probability of its having 
been originally fabricated by the astronomical sons of Misraim. In some few 
zodiacs, Astreea, or the virgin who holds the balance in her hand as an emblem 
of equal justice, is not drawn. Such are the zodiacs of Esne and Dendera. 
Humboldt is of opinion, that although the Romans introduced this constellation 
into their zodiac in the reign of Julius Cesar, still it might have beeti used by the 
Egyptians and other nations of very remote antiquity. 

It is generally supposed that the figure of the balance has been used by all 
nations to denote the equality of the days and nights, at the period of the sun's 
arriving at this sign. It has also been observed, that at this season there is a 
greater uniformity in the temperature of the air all over the earth's surface. 

Others affirm, that the beam only of the balance was at first placed among the 
stars, and that the Egyptians thus honored it as their Nilometer, or instrument 
by which they measured the inundations of the Nile. To this custom of measur- 
ing the waters of the Nile, it is thought the prophet alludes, when he describes 
the Almighty as measuring the waters in the hollow of his hand.— Isa. xl. 12. 

The ancient husbandmen, according to Virgil, were wont to regard this sign 
as indicating the proper time for sowing their winter grain •— 
" But when Astraa's balance, hung on high, 
Betwixt the nights and days divides the sky, 
Then yoke your oxen, sow your winter grain. 
Till cold December comes with driving rain." 

The Greeks declare that the balance was placed among the stars to perpetuate 
the memory of Mochus, the inventor of weights and measures. 

Those who refer the constellations of the Zodiac to the twelve tribes of Israel 
ascribe the Balance to Asher. 



■ 



SERPENS. 

The Serpent. — There are no less than four kinds of ser- 
pents placed among the constellations. The first is the Hydra, 
which is situated south of the Zodiac, below Cancer, Leo 
and Virgo ; the second is Hydrus, which is situated near the 
south pole; the third is Draco, which is situated about the 
north pole ; and the fourth is the serpent called Serpens 
Ophiuchi, and is situated chiefly between Libra and Corona 
Borealis. A large part of this constellation, however, is so 
blended with Ophiuchus. the Serpent-Bearer, who grasps it 
in both hands, that the concluding description of it will be 
deferred until we come to that constellation. 

"The Serpens Ophiuchi winds his spire 
Immense : fewer by ten his figure trace ; 

What star in this consultation marks the southern limit of the Zodiac? How many 
kinds of serpents have been placed amon? the constellations ' Mention them and their 
•ituations. With what is a large part of this constellation blended 7 



MAP. V.] SERPENS. 103 

One of the second rank ; ten shun the sight ; 
And seven, he who bears the monster hides." 

Those stars which lie scattered along for about 25°, in a 
serpentine direction between Libra and the Crown, mark the 
body and head of the Serpent. 

About 10° directly S. of the Crown there are three stars 
of the 3d magnitude, which, with several smaller ones, dis- 
tinguish the head. 

L liuk, of the 2d magnitude, is the principal star in this con- 
stellation. It is situated in the heart, about 10° below those 
in the head, and may be known by its being in a line with, 
and between, two stars of the 3d magnitude — the lower one^ 
marked Epsilon, being 2*°, and the upper one. marked Delta, 
about 5§°from it. The direction of this line is N. N. W. and 
S. S. E. Unuk may otherwise be known by means of a 
small star, just above it, marked Lambda. 

In that part of the Serpent which lies between Corona Bo- 
realis and the Scales, about a dozen stars may be counted, 
of which five or six are conspicuous. 

For the remainder of this constellation, the student is re- 
ferred to Serpentarius. 

" Vast as the starry Serpent, that on high 
Tracks the clear ether, and divides the sky, 
And southward winding from the Northern Wain, 
Shoots to remoter spheres its glittering train." — Statius. 

History.— The Hivites. of the Old Testament, were worshipers of the Ser- 
pent, and were called Ophites. The idolatry of these Ophites was extremely 
ancient, and was connected with Sabeism. or the worship of the host of heaven. 
The heresy of the Ophites, mentioned by Mosheim in his Ecclesiastical History, 
originated, perhaps, in the admission into the Christian church of some remnant 
of the ancient and popular sect of Sabeists, who adored the celestial Serpent. 

According to ancient tradition, Ophiuchus is the celebrated physician iEscu- 
lapius, son of Apollo, who was instructed in the healing art by Chiron the Cen- 
taur ; and the serpent, which is here placed in his hands, is understood by some 
to be an emblem of his sagacity and prudence ; while others suppose it was 
designed to denote his skill in healing the bite of this reptile. Biblical critics 
imagine that this constellation is alluded to in the following passage of the book 
of Job : — 

"By his spirit He hath garnished the heavens; his hand hath formed the 
crooked serpent." Mr. Green supposes, however, that the inspired writer here 
refers to Draco, because it is a more obvious constellation, being nearer the pole 
where the constellations were more universally noticed ; and moreover, because 
it is a more ancient constellation than the Serpent, and the hieroglyphic by which 
the Egyptians usually represented the heavens. 



CORONA BOREALIS. 

The Northern Crown. — This beautiful constellation may- 
be easily known by means of its six principal stars, which 
are so placed as to form a circular figure, very much resem- 

What stars mark the head and body of the Serpent ? Describe the principal star in 
this constellation. How may it he known ' What stars distinguish the head? How- 
many stars may he counted in that part of the constellation which lies between Corona 
Borealis and the Scales ? How may Corona Borc-ulis be easily known I 



104 PICTURE OF THE HEAVENS. [JTJNE. 

bling a wreath or crown. It is situated directly north of the 
Serpent's head, between Bootes on the west, and Hercules 
on the east. 

This asterism was known to the Hebrews by the name ofAtaroth. and by this 
name the stars in Corona Borealis are called, in the East, to this day. 

Alphacca, of the 2d magnitude, is the brightest and mid- 
dle star in the diadem, and about 11°E. of Mirac, in Bootes. 
It. is very readily distinguished from the others both on ac- 
count of its position and superior brilliancy. Alphacca, Arc- 
turus, and Seginus, form nearly an isosceles triangle, the 
vertex of which is at Arcturus. 

This constellation contains twenty-one stars, of which only 
six o-r eight are conspicuous; and most of these are not 
larger than the 3d magnitude. Its mean declination is 30° 
north, and its mean right ascension 235°; its center is 
therefore on the meridian about the last of June, and the first 
of July. 

" And, near to Heh'ce, effulgent rays 
Beam, Ariadne, from thy starry crown : 
Twenty and one her stars; but eight alone 
Conspicuous ; one doubtful, or to claim 
The second order, or accept thr third." 

History. — This beautiful little cluster of ? ,ars is said to be in commemoration 
of a crown presented by Bacchus to Ariadne, the daughter of Minos, second kins 
of Crete. Tl^seus, king of Athens. (1235 B. C.) was shut up in the celebrated 
labyrinth of Crete, to be devoured by the ferocious Minotaur which was confined 
in that place, and which usually fed upon the chosen young men and maidens 
exacted from the Athenians as a yearly tribute to the tyranny of Minos; but 
Theseus slew the monster, and being furnished with a clew of thread by Ariadne, 
who was passionately enamored of him, he extricated himself from the difficult 
windings of his confinement. 

He afterward married the beautiful Ariadne, according to promise, and car- 
ried her a*ay ; but when he arrived at the island of Naxos, he deserted her, 
notwithstanding he had received from her the most honorable evidence of at- 
tachment and endearing tenderness. Ariadne was so disconsolate upon being 
abandoned by Theseus, that, as some say, she hanged herself; but Plutarch wya 
that she lived many years after, and was espoused to Bacchus, who loved her 
with much tenderness, and gave her a crown of seven stars, which, after Lv 
death, was placed among the stars. 

"Resolves, for this the dear engaging dame 
Should shine forever in the rolls of fame ; 
And bids her crown among the stars be placed, 
And with an eternal constellation graced. 
The golden circlet mounts ; and. as it flies. 
Its diamonds twinkle in the distant skies ; 
There, in their pristine form, the gemmy rays 
Between Alcides and the Dragon blaze." 

Manilius, in the first book of his Astronomicon, thus speaks of the Crown. 

; 'Near to Bootes the bright Crown is vie* M 
And shines with stars of different magnitude : 

Where is it situated? Describe the principal star in the primp. What geometrical 
figure ie formed by the stars in this neighborhood ? What are the number und mag- 
nitude of the sturs in this constellation? What are iu mean declination aod right <u 
When is it on our meridian ? 



MAP VI.] URSA MAJOR. 105 

Or piaced in front above the rest displays 
A vigorous light, and darts surprising rays. 
This shone, since Theseus first his faith betray'd, 
The monument of the forsaken maid." 



URSA MINOR. 

The Little Bear. — This constellation, though not re- 
markable in its appearance, and containing but few conspic- 
uous stars, is, nevertheless, justly distinguished from all 
others for the peculiar advantage which its position in the 
heavens is well known to afford to nautical astronomy, and 
especially to navigation and surveying. 

The stars in this group being situated near the celestial 
pole, appear to revolve about it, very slowly, and in circles 
so small as never to descend below the horizon. 

In ail ages of the world, this constellation has been more 
universally observed, and more carefully noticed than any 
other, on account of the importance which mankind early 
attached to the position of its principal star. 

This star which is so near the true pole of the heavens, 
has, from time immemorial, been denominated the North 
Polar Star. By the Greeks it is called Cynosyre ; by the 
Romans, Cynosure^ and by other nations, Alruccabah. 

It is of the 3d magnitude, or between the 2d and 3d, and 
situated a little more than a degree and a half from the true 
pole of the heavens, on that side of it which is toward Cassi- 
opeia and opposite to Ursa Major. Its position is pointed 
out by the direction of the two Pointers, Merak andDubhe. 
which lie in the square of Ursa Major. A line joining Beta 
Cassiopeia?, which lies at the distance of 32° on one side, and 
Megrez, which lies at the same distance on the other, will 
pass through the polar star. 

So general is the popular notion, that the North Polar Star 
is the true pole of the world, that even surveyors and navi- 
gators, who have acquired considerable dexterity in the use 
of the compass and the quadrant, are not aware that it ever 
had any deviation, and consequently never make allowance 
for any. All calculations derived from the observed position 
of this star, which are founded upon the idea that its bearing 
is always due north of any place, are necessarily erroneous, 
since it is in this position only twice in twenty-four hours ; 
once when above, and once when below the pole. 

What renders Ursa Minor an important constellation ? What is its situation with re- 
spect to the North Pole, and how do its stars appear to revolve around this pole ? Why 
has this constellation been more universally observed, in all ages of the world, than any 
other? What is this star denominated ? What are its magnitude and position ? How 
is its position pointed out? How is it situated with respect to Megrez and Beta Cas- 
siopeia? Is it generally considered to be the north pole of the heavens? Are calcuia 
tions ..bunded upon this notion correct' 



106 



PICTURE OF THE HEAVENS. 



[JUNE. 

According to the Nautical Almanac, the mean distance of 
this star from the true pole of the heavens, for the year 1833 
is 1° 34' 53"; and its mean right ascension is 1 hour and 19 
seconds. Consequently, when the right ascension of the 
meridian of any place is 1 hour and 19 sdconds, the star will 
be exactly on the meridian at that time and place, but 1° 34' 
53" above the true pole. Six hours alter, when the right as- 
cension of the meridian is 7 hours and 19 seconds, the star 
will be at its greatest elongation, or 1° 34' 53'' directly west 
of the true pole, and parallel to it, with respect to the horizon \ 
and when the right ascension of the meridian is 13 hours and 
19 seconds, the star will be again on the meridian, but at the 
distance of 1° 34' 53" directly below the pole. 

in like manner, when the right ascension of the meridian is 
19 hours and 19 seconds, the star will be at its greatest east- 
ern elongation, or 1° 34' 53" east of the true pole ; and when 
it has finished its revolution, and the right ascension of the 
meridian is 25 hours and 19 seconds, or, what is the same 
thing. 1 hour and 19 seconds, the star will now be on the 
meridian again, 1° 34' 53" above the pole. 

N. B. The right ascension of rlie meriilian or of the mid-heaven, is the distance 
of the first poinr of Aries from the meridian, at the time and place of observation. 
The riiiht ascension of the meridian for any time is found by adding to the given 
time the sun's righ-: ascension at the same' time, and deducting 24 hours, when 
the sum exceeds 24 hours. 

From the foregoing facts we learn, that from the time the 
star is on the meridian, above the pole, it deviates farther and 
farther from the true meridian, every hour, as it moves to the 
west, for the space of six hours, when it arrives at its great- 
est elongation west, whence it reapproaches the same meri- 
dian below the pole, during the next six hours, and is then 
again on the meridian; being thus alternately half the time 
west of the meridian, and half the time east of it. 

Hence, it is evident that the surveyor who regulates his 
compass by th3 North Polar Star, must take his observation 
when the star is on the meridian, either above or below the 
pole, or make allowance for its altered position in every other 
situation. For the same reason must the navigator, who ap- 
plies his quadrant to this star 1'or the purpose of determining 
the latitude he is in, make a similar allowance, according as 
its altitude is greater or less than the true pole of the hea- 



What is the present distanr e of this star from the true pole of the heavens « What ia 
its mean right ascension ? When is it on the meridian, anil what then is its bearing 
from the pole? What is its situation six hours afterward; What is its situation six 
hours after that? What is its situation when in its third quadrant 1 What do you un- 
derstand by the right, ascension of the meridian, or of the mid-heaven } Hmr> do you 
find the right ascension of the. raid-heavenl In what manner ooes the north star de- 
viate from the meiidian during one revolution? How do these facts concern the sur- 
veyor ? 



MAP VI.] URSA MIXOR. 107 

vens ; for we have seen that it is alternately half the time 
above and half the time below the pole. 

The method of finding the latitude of a place from the al- 
titude of the polar star, as it is very simple, is very often re- 
sorted to. Indeed, in northern latitudes, the situation of this 
star is more favorable for this purpose than that of any other 
of the heavenly bodies, because a single observation, taken 
at any hour of the night with a good instrument, will give 
the true latitude, without any calculation or correction, ex- 
cept that of its polar aberration. 

If the polar star always occupied that point in the heavens which is directly 
opposite the north pole of the earth, it would be easy to understand how laiirude 
could be determined from it in the northern hemisphere; for in this case, to a 
person on the equator, the poles of the world would be seen in the horizon. 
Consequently, the star would appear just visible in the northern horizon, without 
any elevation. Should the person now travel one decree toward the north, 
lie would see one degree below the star, and he would think it had risen one 
degree. 

And since we always see the whole of the upper hemisphere at one view, when 
there is nothing in the horizon to obstruct our vision, it ibllows that if we should 
travel 10° north of the equator, we should see just 10° below the pole, which 
would then appear to have risen 10° ; and should we stop at the 42d degree of 
oorth latitude we should, in like maimer, have our horizon just 42° below the 
pole, or the pole would appear to have an elevation of 42°. Whence we derive 
this general truth : The elevation of the pole of the equator is alicays equal to 
the latitude of the p'ace cf observation. 

Any instrument, then, which will give us the altitude of the north pole, will 
give us also the latitude of' the place. 

The method of illustrating this phenomenon, is given in most treatises on the 
globe, and as adopted by teachers generally, is to tell the scholar that the north 
pole rises higher and higher, as he travels farther and farther toward it. It; 
Jther words, whatever number of degrees he advances tuicard the north pole, 
so many degrees \\ ill it rise above his horizon. This is not only an obvious error 
in principle, bul it misleads the apprehension of the pupil. It is not that the pole 
is elevated, but that our horizon is depressed as we advance toward the north. 
The same objection lies against the artificial globe; for it ought to be so fixed 
that (lie horizon might be raised or depressed, and the pole remain in its own 
invariable position. 

Ursa Minor contains twenty-four stars, including three of 
the 3d magnitude and {bur of the 4th. The seven principal 
stars are so situated as to form a figure very much resembling 
that in the Great Bear, only that the Dipper is reversed, and 
about one half as large as the one in that constellation. 

The first star in the handle, called Cynosura. or Alrucca- 
bah, is the polar slar. around which the rest constantly re- 
volve. The two last in the bowl of the Dipper, correspond- 
ing to the Pointers in the Great Bear, are of the 3d magni- 

Wtay is the method of fibdin? the latitude by the t>olar star often resorted to > Vhv 

is the position of this s;:r liivorabie to this purpi s_- ? // the north star perfectly coin- 

• the north pot, from the equator 1 

Should a " the n.vator. tchere would the star appear 

«!w-u\t ' tr/n-e. io ' the equator I Suppose hi 

mminei - . the num- 

ber ai.,1 ];.- ;.... - I 

principal 6tars form !■■■■■ ,: n I jpper. Deicriur 

the two Itstm the bowl uf the Dipper 



108 PICTURE OF THE HEAVENS [JUNE. 

tude, and situated about 15° from the pole. The brightest of 
them is called Kochab, which signifies an axle or hinge, pro- 
bably in reference to its moving so near the axis of the earth. 

Kochab may be easily known by its being the brightest 
and middle one of the three conspicuous stars forming a row. 
one of which is about 2°. and the other 3°, from Kochab. The 
two brightest of these are situated in the breast and shoulder 
of the animal, about 3° apart, and are called the Guards oi 
Pointers of Ursa Minor. They are on the meridian about 
the 20th of June, but may be seen at all hours of the night, 
when the sky is clear. 

Of the four stars which form the bowl of the Dipper, one 
is so small as hardly to be seen. They lie in a direction to- 
ward Gamma in Cepheus ; but as they are continually 
changing their position in the heavens, they may be much 
better traced out from the map. than from description. 

Kochab is about 25° distant from Benetnasch, and about 
24° from Dubhe, and hence forms with them a very nearly 
equilateral triangle. 

" The Lesser Bear 

Leads from the pole the lucid band : the stars 
Which form this constellation, faintly shine. 
Twice twelve in number ; only one beams forth 
Conspicuous in high splendor, named by Greece 
The Cynosure ; by us, the Polar Star." 
History. — The prevailing opinion is that Ursa Major and Ursa Minor are the 
nymph Calisto and her son Areas, and that they were transformed into bears by 
the enraged and imperious Juno, and afterward translated to heaven by the fa- 
vor of Jupiter, lest they might be destroyed by the huntsmen. 

The Chinese claim that the emperor Hongti. the grandson of Noah, first dis- 
covered the polar star, and applied it to purposes of navigation. It is certain that 
it was used for this purpose in a very remote period of antiquity. From various 
passages in the ancients, it is manifest that the Phenicians steered by Cynosura, 
or the Lesser Bear ; whereas the mariners of Greece, and some other nations, 
steered by the Greater Bear, called Helice. or Helix. 

Lucan, a Latin poet, who nourished about the time of the birth of our Sariour, 

thus adverts to the practice of steering vessels by Cynosura:— 

"Unstable Tyre now knit to firmer ground, 

With Sidon for her purple shells renown'd, 

Safe in the Cynosure their glittering guide 

With well-directed navies stem the tide." 

Rowe's Translation, B. iii. 
The following extracts from other poets contain allusions to the same fact: 
" Phenicia, spurning Asia's bounding strand, 
By the bright Pole star's steady radiance led, 
Bade to the winds her daring sails expand. 
And fearless plough'd old Ocean's stormy bed." 

Maurice's Elegy on Sir W. Jones. 
" Ye radiant signs, who from the ethereal plain 
Sidonians guide, and Greeks upon the main. 
Who from your poles all earthly things explore, 
And never set beneath the western shore." 

Ovid's Tristi*. 

How may Kochab be easily known? What are the position and uame of the two 
orightest of theae ? When are they on the meridian ? How is Kochab situated wits 
fcapeet to Benetnasch and Dubhe » 



MAP V.] SCORPIO. 109 

" Of all yon multitude of golden stars, 
Which the wide rounding sphere incessant bears. 
The cautious mariner relies on none, 
But keeps him to the constant pole alone ' 

Lucan's Pharsalia, B. viii. v. 225. 
Ursa Major and Ursa Minor are sometimes called Triones, and sometimes the 
Greater and Lesser Wains. In Pennington's Memoirs of the learned Mrs. Car- 
ter, we have the following beautiful lines : — 

" Here, Cassiopeia fills a lucid throne. 
There, blaze the splendors of the Northern Crown ; 
While the slow Car, the cold Triones roll 
O'er the pale countries of the frozen pole : 
Whose faithful beams conduct the wandering ship 
Through the wide desert of the pathless deep." 
Thales, an eminent geometrician and astronomer, and one of the seven wise 
men of Greece, who flourished six hundred years before the Christian era, ia 
generally reputed to be the inventor of this constellation, and to have taught th« 
use of it to the Phenician navigators; it is certain that he brought the knowledge 
of it with him from Phenice into Greece, with many other discoveries both in 
astronomy and mathematics. 

Until the properties of the magnet were known and applied to the use of navi- 
gation, and for a long time after, the north polar star was the only sure guide. 
At what time the attractive powers of the magnet were first known, is not certain ; 
they were known in Europe about six hundred years before the Christian era ; 
and by the Chinese records, it is said that its polar attraction was known in that 
country at least one thousand years earlier. 



CHAPTER IX. 

DIRECTIONS FOR TRACING THE C0NSTELLATI0N3 WHICH ARE 
ON THE MERIDIAN IN JULY. 

SCORPIO. 

The Scorpion. — This is the eighth sign, and ninth con- 
stellation, in the order of the Zodiac. It presents one of the 
most interesting groups of stars for the pupil to trace out that 
is to be found in the southern hemisphere. It is situated 
southward and eastward of Libra, and is on the meridian the 
10th of July. 

The sun enters this sign on the 23d of October, but does not reach the constella- 
tion before the 20th of November. When astronomy was fir.-st cultivated in the 
East, the two solstices and the two equinoxes took place when the sun was in 
Aquarius and Leo, Taurus and Scorpio, respectively. 

Scorpio contains, according to Flamsted, forty-four stars 
including one of the 1st magnitude, one of the 2d, and eleven 
of the 3d. It is readily distinguished from all others by the 
peculiar luster and the position of its principal stars. 

Antares is the principal star, and is situated in the heart 

What is the position of Scorpio, among the signs and constellations of the Zodiac 
How is it situated with respect to Libra, and when is it on our meridian? What are 
the number and magnitude of its stars ? How is it l.r.dil distinguished from ali othem. 
Describe the principal star in this constellation. 

10 



110 PICTURE OF THE HEAVENS. [.JULY. 

of the Scorpion, about 19° east of Zubenelgubi, the southern- 
most star in the Balance. Antares is the most brilliant siar 
in that region of the skies, and may be otherwise distinguish- 
ed by its remarkably red appearance. Its declination is about 
26° S. It comes to the meridian about three hours after 
Spica Virginis, or fifty minutes after Corona Boreal is. on the 
10th of July. It is one of the stars from which the moon's 
distance is reckoned for computing the longitude at sea. 

There are four great stars in the heavens, Fomalhaut, Aldnbaran, Regulus. 
and Antaress, which formerly answered to the solstitial and equinoctial points, 
and which were much noticed by the astronomers of the East. 

About Sh° north-west of Antares, is a star of the 2d mag- 
nitude, in the head of the Scorpion, called Graffias. It is but 
one degree north of the earth's orbit. It may be recognized 
by means of a small star, situated about a degree north-east 
of it, and also by its forming a slight curve with two other 
stars of the 3d magnitude, situated below it, each about 3° 
apart. The broad part of the constellation near Graffias, is 
powdered with numerous small stars, converging down to a 
point at Antares, and resembling in figure a boy's kite. 

As you proceed from Antares, there are ten conspicuous 
stars, chiefly of the 3d magnitude, which mark the tail of the 
kite, extending down, first in a south south-easterly direction 
about 17°, thence easterly about S° further, when they turn, 
aod advance about. S° toward the north, forming a curve like 
a shepherd's crook, or the bottom part of the letter S. This 
crooked line of stars, forming the tail of the Scorpion, is very 
conspicuous, and may be easily traced. 

The first star below Antares, which is the last in the back, is of only the 4th 
magnitude. It is about 2° south-east of Antares, and is denoted by the Greek 
name of T. 

Epsilon, of the 3d magnitude, is the second star from Antares. and the first in 
the tail. It is situated about 7° below the ^ tar T, but inclining a little to the east. 

Mil of the 3d magnitude, is the third star from Antares. It is situated 4i° be- 
low Epsilon. It may otherwise be known by means of a small star close "by it, 
on the left. 

Zeta. of about the same magnitude, and situated about as fir below Mu, is the 
fourth star from Antares. Here the line turns suddenly to the east. 

Eta, also of the 3d magnitude, is the fifth star from Antares. and about 3'P east 
of Zeta. 

Theta, of the same magnitude, is the sixth star from Antares. and about 4h° 
east of Eta. Here, the line turns again, curving to the north, and terminates fn 
a couple of stars. 

Iota is the seventh star from Antares, 3h° above Theta, curving a little to the 
'left. It is a star of the 3d magnitude, anufmay be known by means of a small 
star, almost touching it, on the east. 

Kappa, a star of equal' brightness, is less than 2° above lota, and a little to the 
right. 

How is Antares otherwise distinguished^ Wh.it is its declination? Whjt is the 
time of it3 passing the meridian ? What naut;cal importance is attached to its position ? 
Describe Graffias ? How may it be recognized ? What is the appearance of the constel- 
lation between Graffias and Antares ? How many conspicuous st,irs below Antares? 
What are their magnitude and general direction ? Describe the first star below Anta- 
res. Describe the second star be 1 ow Antares. Describe the third star, and tellhoio it 
may be krunon. Describe the fourth. Describe the fifth. Describe Theta. Describe 
Iota. Describe Kappa. 



MAP V.] SCORPIO. Ill 

Lesuth. of the 3d magnitude, is the brightest of the two last in the tail, and is sit* 
uated about 3~ above Kappa, still further to the right. It may readily be known 
by means of a smaller star, close by it. on the west. 

This is a very beautiful group of stars, and easily traced 
out in the heavens. It furnishes striking evidence of the fa- 
cility with which most of the constellations may be so accu- 
rately delineated, as to preclude every thing like uncertainty 
in the knowledge of their relative situation. 

•• The heart with luster of amazing force, 
Refulgent vibrates; faint the other parts. 
And ill-defined by stars of meaner note." 

History. — This sign was anciently represented by various symbols, some- 
times by a make, and sometimes by a crocodile ; but most commonly by the 
scorpion. Tiiis ia>t symbol is found "on the Mithraic monuments, which is pretty 
good evidence that these monuments Avere constructed when the vernal equinox 
accorded with Taurus. 

On both the zodiacs of Dendera. there are rude delineations of this animal : 
that on the portico differs considerably from that on the other zodiac, now in the 
Louvre. 

Scorpio was considered by the ancient astrologers as a sign accursed. The 
Egyptians fixed the entrance of the sun into Scorpio as the commencement of 
the feign of Typhon. when the Greeks fabled the death of Orion. When the sun 
was in Scorpio, in the month of Athyr, as Plutarch informs us, the Egyptians 
inclosed the body of their god Osiris in an ark, or chest, and during this cere- 
mony a great annual festival was celebrated. Three days after the priests had 
inclosed Osiris in the ark, they pretended to have found him again. The death 
of Osins. then, was lamented 'when the sun in Scorpio descended to the lower 
hemisphere, and when he arose at the vernal equinox, then Osiris was said to be 
born anew. 

The Egyptians or Chaldeans, who first arranged the Zodiac, might have placed 
Scorpio in this part of the heavens to denote tliat when the sun enters this sign, 
the diseases incident to the fruit season would prevail ; since Autumn, which 
abounded in fruit, often brought with it a great variety of diseases, and might be 
thus fitly represented by that venomous animal, the scorpion, who, as he recedes, 
wounds with a sting in his tail. 

Mars was the tutelary deity of the Scorpion, and to this circumstance is owing 
all that jargon of the astrologers, who say that there is a great analogy between 
the malign "influence of the planet Mars and this sign. To this also is owing the 
doctrine of the alchemists, that iron, which metal they call Mars, is under the 
dominion of Scorpio ; so that the transmutation of it into gold can be effected- 
only when the sun is in this sign. 

The constellation of the Scorpion is very ancient. Ovid thus mentions it in his 
beautiful fable of Phaeton : — 

'• There is a place above, where Scorpio bent, 
In tail and arms surrounds a vast extent ; 
In a wide circuit of the heavens he shines. 
And fills the place of two celestial signs." 

According to Ovid, this is the famous scorpion which sprang out of the earth 
at the command of Juno, and stuu<r Orion ; of which wound he died. It was in 
this way the imperious goddess chose to punish the vanity of the hero and the 
hunter, for boasting that there was not on earth any animal which he could not 
conquer. 

'• Words that provoked the gods once from him fell, 

• No beasts so fierce.' said he, ' but I can quell ;' 

When lo ! tiie earth a baleful scorpion sent, 

To kill Latona was the dire intent ; 

Orion saved her. though himself was slain, 

liut did for that a spacious place obtain 

In heaven : ' to thee my life,'' said she, ' teas dear, 

And for thy merit shine illustrious there.' " 

Desa He Lcsuih. 



112 PICTURE OF THE HEAVENS. [JULY. 

Although both Orion and Scorpio were honored by the celestials with a place 
among the stars, yet their situations were so ordered that when one rose the 
other should set, and vice versa; so that they never appear in the same hemi- 
sphere at the same time. 

In the Hebrew zodiac this sign is allotted to Dan, because it is written, " Dan 
shall be a serpent by the way, an adder in the path." 



HERCULES. 

Hercules is represented on the map invested with the skin 
of" the Nemcean Lion, holding a massy club in his right hand, 
and the three-headed dog Cerberus in his left. 

He occupies a large space in the northern hemisphere, 
with one foot resting on the head of Draco, on the north, and 
his head nearly touching that of Ophiuchus, on the south. 
This constellation extends from 12° to 50° north declination, 
and its mean right ascension is 255° ; consequently its center 
is on the meridian about the 21st of July. 

It is bounded by Draco on the north, Lyra on the east, 
Ophiuchus or the Serpent-Bearer on the south, and the Ser- 
pent and the Crown on the west. 

It contains one hundred and thirteen stars, including one 
of the 2d. or of between the 2d and 3d magnitudes, nine of the 
3d magnitude, and nineteen of the 4th. The principal star 
is Ras Algethi, and is situated in the head, about 25° south-east 
of Corona Borealis. It may be readily known by means of 
another bright star of equal magnitude, 5° east south-east of 
it, called Ras Alhague. Ras Alhague marks the head of 
Ophiuchus, and Ras Algethi that of Hercules. These two 
stars are always seen together, like the bright pairs in Aries, 
Gemini, the Little Dog, &c. They come to our meridian 
about the 28th of July, near where the sun does, the last of 
April, or the middle of August. 

About midway between Ras Algethi on the south-east, and Ariadne's Crown on 
the north-west, may be seen Beta and Gamma, two stars of the 3d magnitude, sit- 
uated in the west shoulder, about 3° apart. The northernmost of these two is 
called Rutilicus. 

Those four stars in the shape of a diamond, 8° or 10° south-west of the two in 
the shoulder of Hercules, are situated in the head of the serpent. 

About 1-2° E. N. E. of Rutilicus, and 10±° directly north of Ras Algethi, are 
two stars of the 4th magnitude, in the ea.-t shoulder. They may be known by 
two very minute stars a little above them on the left. The two stars in each 
shoulder of Hercules, with Ras Algethi in the head, form a regular triangle. 

The left, or eait arm of Hercules, which prasps the triple-headed monster Cer. 
berus, may be traced by means of three or four stars of the 4th magnitude, situa. 

How is the constellation Hercules represented? What space does it occupy, and 
what is its situation in the heavens? What are iU declination and right ascension? 
When is its center on the meridian ? How is it bounded ? What are the number and 
magnitude of its stars ? Describe the principal star. What do Ras Algethi and Ras 
Alhague serve to mark ? When are they on our meridian ? Describe the situation of 
Beta and Gamma. What is the northernmost of these two called? What four start 
are situated, s c or 10« S. W. of the two in the sh/>ulder ( Describe the stars in the east 
shoulder. How may these be known ? What geometrical figure do the stars in the 
head and sltonlders of Lercu'cs forml How may the left arm of Hercules be tra- 
ced} 



MAP V.] HERCULES. 1 13 

ted in a row 3° and 4° apart, extending from the shoulder, in a north-easterly di- 
rection. That small cluster, situated in a triangular form, about 14° north-east of 
Ras Algethi, and 13° east south-east of the left shoulder, distinguish the head of 
Cerberus. 

Eighteen or 20 r ' north-east of the Crown, are four stars of the 3d and 4th mag- 
nitudes, forming an irregular square, of which the two southern ones are about 
4° apart, and in a line 6° or 7° south of the two northern ones, which are nearly 
7° apart. 

Pi, in the north-east corner, may be known by means of one ortwo other smaK 
Btars. close by it, on the east. Eta, in the north-west corner, may be known by 
its being in a row with two smaller stars, extending toward the north-west, and 
about 4° apart. The stars of tbe 4th magnitude, just south of the Dragon's head, 
point out the left foot and ankle of Hercules. 

Several other stars, of the 3d and 4th magnitudes, may be traced out in this 
constellation, by x-eference to the map. 

History.— This constellation is intended to immortalize the name of Hercules, 
the Thenan, so celebrated in antiquity for his heroic valor and invincible prow- 
ess. According to the ancients, there were many persons of this name. Of all 
these, the son of Jupiter and Alcmena is the most celebrated, and to him the ac- 
tions of the others have been generally attributed. 

The birth of Hercules was attended with many miraculous events. He was 
brought up at Tirynthus, or at Thebes, and before he had completed his eighth 
month, the jealousy of Juno, who was intent upon his destruction, sent two. 
snakes to devour him. Not terrified at the sight of the serpents, he boldly seized 
them, and squeezed them to death, while his brother Ipaicies alarmed the house 
with his frightful shrieks. 

He was early instructed in the liberal arts, and soon became the pupil of the 
centaur Chirou, under whom he rendered himself the most valiant and accom- 
plished of all the heroes of antiquity. In the 13th year of his age, he commen- 
ced his arduous and glorious pursuits. He subdued a lion that devoured the 
flocks of his supposed father, Amphitryon. After he had destroyed the lion, he 
delivered his country from the annual tribute of a hundred oxen, which it paid 
to Erginus. 

As Hercules, by the will of Jupiter, was subjected to the power of Eurystheus, 
and obliged to obey him in every respect, Eurystheus, jealous of his rising fame 
and power, ordered him to appear at Mycenae, and perform the labors which, by 
prioi-ity of birth, he was empowered to impose upon him. Hercules refused;, 
but afterward consulted the oracle of Apollo, and was told that he must be sub- 
servient, for twelve years, to the will of Eurystheus, in compliance with thv. 
commands of Jupiter ; and that, after he had achieved the most celebrated la- 
bors, lie should be reckoned iu the number of the gods. So plain an answer de- 
termined him to go to Mycenae, and to bear with fortitude whatever gods or men 
should impose upon him. Eurystheus, seeing so great a man totally subjected 
to him, and apprehensive of so powerful an enemy, commanded him to achieve 
a number of enterprises the most difficult and arduous ever known, generally 
called the Twelve Labors op Hercules. Being furnished with complete ar- 
mor by the favor of the gods, he boldly encountered the imposed labors. 

1. lie subdued the Nemaean Lion in his den, and invested himself with his 
skin. 

2. He destroyed the Lernaean Hydra, with a hundred hissing heads, and dip- 
ped his arrows in the gall of the monster to render their wounds incurable. 

3. He took alive the stag with golden horns and brazen feet, so famous for ita 
incredible swiftness, after pursuing it for twelve months, and presented it, un- 
hurt, to Eurystheus. 

4. He took alive the Erymanthian Boar, and killed the Centaurs who opposes 
him. 

5. He cleansed the stables of Augias. in which 3000 oxen had been confined for 
many years. 

(5. He killed the carniverous birds which ravaged the country of Arcadia, and 
fed on human flesh. 

7. lie took alive, and brought into Peloponnesus, the wild bull of Crete, whicb 
no mortal durst look upon. 



How is the head of Cerberus distinguished ? There are four s:ars in the form of i 
irrtgu'ar square, in the body of Herat ex— describe them. Describe the suuatior ■ 
IH. Describe t/te situation of Eta. What start poi-it out the left fool of Hercules} 

10* 



114 PICTURE OF THE HEAVENS. [JULY. 

8. He obtained for Eurysfheus the mares of Diomedes, which fed on human 
flesh, after having given their owner to be first eaten by them. 

9. He obtained the girdle of the queen of the Amazons, a formidable nation of 
warlike females. 

10. He killed the monster Geryon, king of Gades, and brought away his nu- 
merous flocks, which fed upon human flesh. 

11. He obtained the golden apples from the garden of the Hesperides, which 
were watched by a dragon. 

12. And finally, he brought up to the earth the three-headed dog Cerberus, the 
guardian of the entrance to the infernal regions. 

According to Dupuis, the twelve labors of Hercules are only a figurative rep- 
resentation of the annual course of the sun through the twelve signs of the Zodiac ; 
Hercules being put for the sun, inasmuch as it is the powerful planet which ani- 
mates and imparts fecundity to the universe, and whose divinity has been hon- 
ored, in every quarter, by temples and altars, and consecrated in the religious 
strains of all nations. 

Thus Virgil, in the eighth book of his ^neid, records the deeds of Hercules, 
and celebrates his praise : — 

'•The lay records the labors, and the praise, 

And all the immortal acts of Hercults. 

First, how the mighty babe, when swath'd in bands, 

The serpents strangled with his infant hands ; 

Then, as in years and matchless force he grew, 

The CEchalian walls and Trojan overthrew 

Besides a thousand hazards they relate, 

Procured by Juno's and Eurystheus' hate. 

Thy hands, unconquer'd hero, could subdue 

The cloud-horn Centaurs, and the monster crew ; 

Nor thy resistless arm the bull withstood; 

Nor he, the roaring terror of the wood. 

The triple porter of the Stygian seat 

With Lolling tongue lay fawning at thy feet, 

And. seized with fear, forgot the mangled meat. 

The infernal waters trembled at thy sight : 

Thee, god, no face of danger could affright; 

Nor huge Typhaeus, nor the unnumber'd snake, 

Increased with hissing heads, in Lerna's lake." 

Besides these arduous labors which the jealousy of Eurystheus imposed upon 
him, he also achieved others of his own accord, equally celebrated. Before he 
delivered himself up to the king of Mycente he accompanied the Argonauts to 
Colchis. He assisted the gods in their wars against the giants, and it was through 
him alone that Jupiter obtained the victory. He conquered Laomedon and pil- 
laged Troy. 

At three different times he experienced fits of insanity. In the second, he slew 
the brother of his beloved Iole ; in the third he attempted to carry away the sa- 
cred tripod from Apollo's temple at Delphi, for which the oracle told him he 
must be sold as a slave. He was sold accordingly to Omphale, queen of Lydi.i, 
who restored him to liberty, and married him. After this he returned to Pelo- 
ponnesus, and re-established on the throne of Sparta his friend Tyndarus, who 
had been expelled by Hippocoon. He became enamored of Dejanira. whom, 
after having overcome all his rivals, he married ; but was obliged to leave his 
father-in-law's kingdom, because he had inadvertently killed a man with a blow 
<.! his fist. He retired to the court of Ceyx, king of Trachina, and in his way was 
snipped by the streams of the Evenus, where he slew the Centaur Nessus, for 
presuming to offer indignity to his beloved Dejanira. The Centaur, on expiring, 
gave to Dejanira the celebrated tunic which afterward caused the death of Her- 
cules. " This tunic." said the expiring monster, '• has the virtue to recall a hus- 
band from unlawful love." Dejanira. Yearing lest Hercules should relapse again 
hi to love for the beautiful Iole! save him the fatal tunic, which was so infected 
with the poison of t lie Lernsean Hydra, that he had no sooner invested himself 
with it. than it began to penetrate his bones, and to boil through all his veins 
He attempted to pull it off, but it was too late. 

41 As the red iron hisses in the flood, 

So boils the venom in his curdling blood. 

Now with the greedy flame his entrails glow, 

And livid sweats down all his body flow ; 



MAP V.] SEP,PENTARIUS. 115 

The crackling nerves, burnt up. are burst in twain, 
The lurking venom melts his swimming brain." 
As the distemper was incurable, he implored the protection of Jupiter, gave 
his bow and arrows to Philoctetes, and erected a large burning pile on the top of 
Mount CEta. He spread on the pile the skin of die Nemaean lion, and laid him- 
self down upon it. as on a bed. leaning his head upon his club. Philoctetes set 
fire to the pile, and the hero saw himself, on a sudden, surrounded by the most 
appalling flames ; yet he did not betray any marks of fear or astonishment. Ju- 
piter saw him from heaven, and told the surrounding gods, who would have 
drenched the pile with tears, while they entreated that he would ra ; se to the 
Bkies the immortal part of a hero who had cleared the earth from so many mon- 
sters and tyrants ; and thus the thunderer spake : — 

•• Be all your fears forborne : 

The CEtean fires do thou, great hero, scorn. 

Who vanquish'd all things shall subdue the flame 

That part alone of gross maternal frame 

Fire shall devour ; while what from me he drew 

Stiall live immortal, and its force subdue : 

Tha\ when he's dead. I'll raise to realms above ; — 

Mav all the powers the righteous act approve." 

Ovid's Met. lib. ix. 
Accordingly, after the mortal part of Hercules was consumed, as the ancient 
poets say, he was carried up to heaven in a chariot drawn by four horses. 
" Quern pater omnipotent inter cava nubila raptum, 
Quadrijugo curru radiantibus iutulit astris." 

" Almighty Jove 

In his swift car his honor'd o'ffspring drove ; 
Higli o'er the hollow clouds the coursers fly, 
And lodge the hero in the starry sky." 

Ovid's Met. lib. ix. v. 271. 



SERPENTARIUS, VEL OPHIUCHUS. 

The Serpent-Bearer is also called iEsculapius, or the 
god of medicine. He is represented as a man with a vene- 
rable beard, having both hands clenched in the folds of a 
prodigious serpent, which is writhing in his grasp. 

The constellation occupies a considerable space in the mid- 
heaven, directly south of Hercules, and west of Taurus Po- 
niatowski. Its center is very nearly over the equator, oppo- 
site to Orion, and comes to the meridian the 26th of July. It 
contains seventy-four stars, including one of the 2d magni- 
tude, five of the 3d, and ten of the 4th. 

The principal star in Serpentarius is called Ras Alhague. 
It is of the 2d magnitude, and situated in the head, about 5° 
E. S. E. of Ras Algethi, in the head of Hercules. Ras Al- 
hague is nearly 13° N. of the equinoctial, while Rho, in the 
southern foot, is about 25° south of the equinoctial. These 
two stars serve to point out the extent of the constellation 
from north to south. Ras Alhague comes to the meridian 
on the 2Sth of July, about 21 minutes after Ras Algethi. 

How i> the constellation Serpentarius represented ? What is its extent, and where 
i«t it situated? When is its center on the meridi.-in? What are the number and mag- 
nitude of its stars i What arc the name and position of its principal star? What two 
•tars mark the extremes of the constellation, north and south ; When is Kas Alhague 
on the meridian? 



116 PICTURE OF THE HEAVENS. [JULY. 

About 10° S. W. of lias Alhague are two small stars of the 4ih magnitude, 
scarcely more than a degree apart. They distinguish the left or west shoulder. 
The northern one is marked Iota, and the other Kappa. 

Eleven or twelve degrees S. S. E. of Ras Alhague are two other stars of the 3d 
magnitude, in the east shoulder, and about 2° apart. The upper one is called 
Cheleb. and the lower one Gamma. These stars in the head and shoulders of 
Serpentarius. form a triangle, with the vertex in Ras Alhague, and pointing to- 
ward the north-east. 

About 4° E. of Gamma, is a remarkable cluster of four or 
five stars, in the form of the letter V, with the open part to 
the north. It very much resembles the Hyades. This beau- 
tiful little group mark the face of Taurus Poniatowski. The 
solstitial colure passes through the equinoctial about 2° E. of 
the lower star in the vertex of the V. The letter name of this 
star is k. There is something remarkable in its central posi- 
tion. It is situated almost exactly in the mid-heavens, being 
nearly equidistant from the poles, and midway between the 
vernal and autumnal equinoxes. It is, however, about one 
and a third degrees nearer the north than the south pole, and 
about two degrees nearer the autumnal than the vernal equi- 
nox, being about two degrees west of the solstitial colure. 

Directly south of the V, at the distance of about 12°, are two very small stars, 
about 2° apart, situated in the right hand, where it grasps the serpent. About 
half-way between, and nearly in a line with, the two in the hand and the two in 
the shoulder, is another star of the 3d magnitude, marked Zeta, situated in the 
Serpent, opposite the right elbow. It may be known by means of a minute *tar 
just under it. 

Marsic, in the left arm. is a star of the 4th magnitude, about 10° S. W. of Iota 
and Kappa. About 7° farther in the same direction are two stars of the 3d mag- 
nitude, situated in the hand, and a little more than a degree apart. The upper 
one of the two, which is about 16° N. of Graffias in Scorpio, is called Yed ; the 
other is marked Epsilon. These two stars mark the other point in the folds of 
the monster where it is grasped by Serpentarius. 

The left arm of Serpentarius may be easily traced by means of the two stars 
in the shoulder, the one (Marsic) near the elbow, and the two in the hand ; all 
lying nearly in a line N. N. E. and S. S. W. In the same manner may the right 
arm be traced, by stars very similarly situated : that is to say, first by the two in 
the east shoulder, just west of the V, thence 8° in a southerly direction inclining 
a little to the east, by Zeta, (known by a little star right under it,) and then by the 
two small ones in the right hand, situated about 6° below Zeta. 

About 12° from Antares, in an easterly direction, are two stars in the right foot, 
about 2° apart. The largest and lower of the two. is on the left hand. It is of 
between the 3d and 4th magnitudes, and marked Rho. There are several other 
stars in this constellation of the 3d and 4th magnitudes. They may be traced out 
from the maps. 

'• Thee, Serpentarius, we behold distinct, 
With seventy-four refulgent stars ; and one 
Graces thy helmet, of the second class : 
The Serpent, in thy hand gmsp'd, winds his spire 
Immense ; fewer by ten his figure trace ; 

Describe, the stars in the west shoulder of Serpentarius. What stirs distinguish the 
east shoulder? Hoio are these tioo stars denominated? What is the relative position 
of the stars in the head and shoulders! What remarkable cluster of stars in this neigh- 
borhood ? To what constellation does this group belong? How is this cluster situ itod 
with respect to the solstitial colure? What is remarkable in the central position of 
Kappa ? Describe the stars in the right hand of Serpentarius. Describe the situation 
of Zeta. Describe Marsic, and the two stars in the lc r t hand. Which of the two is 
called Yed, and hoio is it situated } How may the. left arm of Serpentarius be traced? 
How may the right arm be traced ? Describe the stars in the right foot of Serpenta- 
rius. What other stars may be traced out in this constellation ? 



MAP. VI.] DRACO. 117 

One of the second rank ; ten shun the sight ; 

And seven, he who bears the monster hides." — Eudosia. 
History. — This constellation was known to the ancients twelve hundred years 
before the Christian era. Homer mentions it. It is thus referred to in the As- 
tronomicon of Manilius : — 

" Next, Ophiuchus, strides the mighty snake, 

Untwists his winding folds, and smooths his back, 

Extends his bulk, and o'er the slippery scale 

His wide-stretch'd hands on either side prevail 

The snake turns back his head, and seems to rage : 

That war must last where equal power prevails." 

JSsculapius was the son of Apollo, by Coronis, and was educated x>y Chiron 

the Centaur in the art of medicine, in which he became so skillful, that he was 

considered the inventor and god of medicine. At the birth of vEsculapius, the 

inspired daughter of Chiron uttered, " in sounding verse," this prophetic strain ■ 

" Hail, great physician of the world, all hail ! 

Hail, mighty infant, who, in years to come, 

Shall heal the nations and defraud the tomb ! 

Swift be thy growth ! thy triumphs anconfined ! 

Make kingdoms thicker, and increase mankind : 

Thy daring art shall animate the dead. 

And draw the thunder on thy guilty head: 

Then shalt thou die, but from the dark abode 

Rise up victorious, and be twice a god." 
He accompanied the Argonauts to Colchis, in the capacity of physician. He is 
said to have restored many to life, insomuch that Pluio complained to Jupiter, 
that his dark dominion was in danger of being depopulated by his art. 

iEsculapius was worshiped at Epidaurus, a city of Peloponnesus, and hence 
he is styled by Milton, 4, the god in Epulaurus." Being sent for to Rome in the 
time of a plague, he assumed the form of a serpent and accompanied the ambas- 
sadors, but though thus changed, he was JEsculapius still, in serpent e deus — 
the deity in a serpent, and under that form he continued to be worshiped at 
Rome. The cock and the serpent were sacred to him, especially the latter. The 
ancient physicians used them in their prescriptions. 

One of the last acts of Socrates, who is accounted the wisest and best man of 
Pagan antiquity, was to offer acock to JEsculapius. He and Plato were both 
idolaters ; they conformed, and advised others to conform, to the religion of their 
country ; to gross idolatry and absurd superstition. If the wisest and most 
learned were so blind, what must the foolish and ignorant have been ? 



CHAPTER X. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE MERIDIAN IN AUGUST. 

DRACO. 

The Dragon. — This constellation which compasses a large 
circuit in the polar regions by its ample folds and contortions, 
contains many stars which may be easily traced. 

From the head of the monster, which is under the foot of 
Hercules, there is a complete coil tending eastward!}-, about 
17° N. of Lyra ; thence he winds down northerly about 14° 

What is the .situation of the constellation Draco? Describe, if you please, the van 
oq» coils of the Dragon. 



118 PICTURE OF THE HEAVENS. [AUG. 

to the second coil, where he reaches almost to the girdle of 
Cephens, then he loops down somewhat in the shape of the 
letter U. and makes a third coil about 15° below the first 
From the third coil he holds a westerly course for about 13°, 
then goes directly down, passing between the head of the 
Lesser and the tail of the Greater Bear. 

This constellation contains eighty stars, including two of 
the 2d magnitude, three of the 3d, and sixteen of the 4th. 

'• The Dragon next, winds like a mighty stream ; 
Within its ample folds are eighty stars, 
Four of the second order. Far he waves 
His ample spires, involving either Bear.' 

The head of the Dragon is readily distinguished by means 
of four stars, 3°, 4°, and 5° apart, so situated as to form an 
irregular square ; the two upper ones being the brightest, 
and both of the 2d magnitude. The right-hand upper one, 
called Etanin, has been rendered very noted in modern as- 
tronomy from its connection with the discovery of a new law 
in physical science, called the Aberration of Light. 

The letter name of this star is Gamma, or Gamma Draco- 
nis; and by this appellation it is most frequently called. The 
other bright star, about 4° from it on the left, is Rastaben. 

About 4° W. of Rastaben, a small star may, with close at- 
tention, be discerned in the nose of the Dragon, which, with 
the irregular square before mentioned, makes a figure some- 
what resembling an Italic V, with the point toward the west, 
and the open part toward the east. The small star in the 
nose, is called Er Rakis. 

The two small stars 5° or 6° S. of Rastaben are in the left foot of Hercules. 

Rastaben is on the meridian nearly at the same moment 
with Ras Alhague. Etanin, 40° N. of it, is on the meridian 
about the 4th of August, at the same time with the three 
western stars in the face of Taurus Poniatowski, or the V. It 
is situated less than 2° west of the solstitial colure, and is 
exacily in the zenith of London. Its favorable position has 
led English astronomers to -watch its appearance, for long 
periods, with the most exact and unwearied scrutiny. 

In the year 1725, Mr. Molynenx and Dr. Bradley fitted up a very accurate and 
costly instrument, in order to discover whether the fixed stars had any sensible 
parallax, while the earth moved from one extremity of its orbit to the other; or 
which is the same, to determine whether the nearest fixed stars are situated at 
such an immense distance from the earth, that any star which is seen this night 
directly north of us, will, six months hence, when we shall have gone 190 mil- 

What is the course of the monster from the third coil? What are the number and 
magnitude of the stars contained in this constellation' How is the head of the Dra- 
gon distinguished? Which star is called Etanin, and for what is it noted' By what 
other appellation is it generally known ? What sta-s in the head of Dr:iro fo-m the let- 
ter V, and how is it situated? When is Rastaben on the meridian > When is Etanin 
on the meridian, and what stars in this region culminate at the same time? How L» 
Rastaben situated with respect to the solstitial colure and the zenith of London ' 



MAP VI.] 



DRACO. 



119 



lions of miles to the eastward of the place Ave are now in, be then seen exactly 
north of us still, without changing its position so much as the thickness of a 
spider's web. 

These observations were subsequently repeated, with but little intermission, 
for twenty years, by the most acute observers in' Europe, and with telescopes 
varying: from 12 feet to 36 feet in length. In the mean time, Dr. Bradley had the 
honor of announcing to the world the very nice discovery, that the motion of 
light, combined with the progressive motion of the earth in its orbit, causes the 
heavenly bodies to be seen in a different position from what they would be, if 
the ei/e icere at rest. Thus was established the princiole of the Aberration of 
Light. 

This principle, or law, now that it is ascertained, seems not only very plain, 
but self-evident. For if light be progressive, the position of the telescope, in order 
to receive the ray, must be different from what it would have been, if light had ' 
been instantaneous, or if the earth stood still. Hence the place to which the tel- 
escope is directed, will be different from the true place of the object. 

The quantity of this aberration is determined by a simple proposition. The 
earth describes 59' S" of her orbit in a dav = 354S", and a ray of light comes 
from the sun to us in S' 13"= 493" : now 24 hours or SWOO" : 493" : : 354?" : 
22" ; which is the change in the star's place, arising from the cause above men- 
tioned. 

Of the four stars forming the irregular square in the head, the lower and right- 
hand one is 5£° N. of Etanin. It is called Grumium, and is of the 3d magnitude. 
A few degrees E. of the square, may be seen, with a little care, eight stars of the 
5th magnitude, and one of the 4th, which is marked Omicron, and lies 3° E. of 
Grumium. This group is in the first coil of the Dragon. 

Tiie second coil is about 13° below the first, and may be recognized by means 
of four stars of the 3d and 4th magnitudes, so situated as to form a smali square, 
about half the size of that in the head. 

The brightest of them is on the left, and is marked Delta. A line drawn from 
Rastaben through Grumium. and produced about 14°. will point it out. Aline 
drawn from Lyra through Zi Draconis, and produced 10° further, will point ou-t 
Zeta, a star of the 3d magnitude, situated in the third coil. Zeta may otherwise 
be known, by its being nearly in a line with, and midway between, "Etanin aud 
Kochab. From Zeta. "the remaining stars in this constellation are easily traced. 

Eta, Theta, and Asich. come next ; all stars of the 3d magnitude, and at the 
distance, severally, of 6°, 4°, and 5° from Zeta. At Asich. the third star from 
Zeta. the tail of the Dragon makes a sudden crook. Tkuban, Kappa, and Gian- 
sar follow next, and complete the tail. 

Thuban is a bright star of the 2d magnitude, 11° from 
Asicn. in a line with, and about midway between, Mizar and 
the southernmost guard in the Little Bear. By nautical men 
this star is called the Dragoii's Tail, and is considered of 
much importance at sea. It is otherwise celebrated as being 
formerly the north polar star. About 2,300 years before 
the Christian era. Thuban was ten times nearer the true 
pole of the heavens than Cynosura now is. 

Kappa is a star of the 3d magnitude, 1CP from Alpha, between Meirrez and the 

Sole. Mizar and Megrez, in the tail of the Great Bear. form, with Thuban and 
iappa. in the tail of the .Dragon, a large quadrilateral figure, whose longest side 
is from Megrez to Kappa. 

ar, the last star in the tail, is between the 3d and 4rh magnitudes, and 5° 
from Kappa. The two pointers will also point out Giansar, lying at the distance 
of little more than S° from them, and in the direction of the pole. 



e the stars in the first cuil of Draco. Describe the stars in the second coil. 

'he brightest of this zrnup called, and how may it be pointed out] What is 

of the third oil. and how may it ce found? How e sc may Zela be 

• next to Ze;a, in this constellation ? What stars follow 

I'm.han. I'.v what other name is this star known, and Ibr what is it 

Phuban within ten minutes of the pole' 

ire do Mizar and .ilr^,rz. in the tail of the Great Bear, form with Thuban 

■ tail of the Dragon •' Describe the position of Giansar, and tell how 

•d OUl. 



120 PICTURE OF THE HEAVENS. [AUG. 

,; Here tie vast Dragon twines 

Between the Bears, and like a river winds— 
The Bears, that still with fearful caution keep, 
Untinged beneath the surface of the deep." 

Warton's Virgil^ G. i. 

History.— Whoever attends to the situation of Draco, surrounding, as it does? 
the pole of the Ecliptic, will perceive that its tortuous windings are symbolical 
of the oblique course of the stars. Draco also winds round the pole of the world, 
as if to indicate, in the symbolical language of Egyptian astronomy, the motion 
of the pole of the Equator around the pole of the Ecliptic, produced by the pre- 
cession of the heavens. The Egyptian hieroglyphic for the heavens, was a ser- 
pent, whose scales denoted the stars. When astronomy first began to be culti- 
vated in Chaldea, Draco was the polar constellation. 

Mycologists, however, give various accounts of this constellation ; by some 
it is represented as the watchful dragon which guarded the golden apples in the 
famous garden of the Hesperides,* near Mount Atlas in Africa, and was slain by 
Hercules. Juno, who presented these apples to Jupiter on the day of their nup- 
tials, took Draco up to heaven, and made a constellation of him, as a reward for 
his faithful services. Others maintain that in the war with the giants, this dragon 
was brought into combat, and opposed to Minerva, who seized it in her hand, and 
hurled it, twisted as it was, into the heavens round the axis of the world, before 
it had time to unwind its contortions, where it sleeps to this day. Other writers 
of antiquity say, that this is the dragon killed by Cadmus, who was ordered by 
his father to go in quest of his sister Europa, whom Jupiter had carried away, 
and never to return to Phenicia without her. 

K When now Agenor had his daughter lost, 
He sent his son to search on every coast ; 
And sternly bade him to his arms restore 
The darling maid, or see his face no more." 

His search, however, proving fruitless, he consulted the oracle of Apollo, and 
was ordered to build a city where he should see a heifer stop in the grass, and 
to call the country Boeotia. He saw the heifer according to the oracle, and as he 
wished to render thanks to the god by a sacrifice, he sent his companions to 
fetch water from a neighboring grove. The waters were sacred to Mars, and 
guarded by a most terrific dragon, who devoured all the messengers. Cadmus, 
tired of their seeming delay, went to the place, and saw the monster still feeding 
on their flesh. 

" Deep in the dreary den, conceal'd from day, 
Sacred to Mars, a mighty dragon lay, 
Bloated with poison to a monstrous size : 
Fire broke in flashes when he glanced his eyes ; 

* Those who attempt to explain the mythology of the ancients, observe that the Hes 
perides were certain persons who had an immense number of flocks ; and that the 
ambiguous Greek word firi\ov t melon, which sometimes signifies an apple and some- 
times a sheep, gave rise to the fable of the golden apple of these gardens. 

The "Hesperian gardens famed of old," as Milton observes, were so called from 
Hesperus Vesper, because placed in the west, under the evening star. Some suppose 
them to have been situated near Mount Atlas, in Africa ; others maintain that they 
were the isles about Cape Yerd, whose most westerly point is still called Hespcrium 
Cornu. the Horn of the Hesperides.; while others contend, that they were the Canary 
Islands. 

Atlas, said to have been contemporary with Moses, was king of Mauritania, in the 
nonh part of Africa, and owner of a thousand flocks of every kind. For refusing hos- 
pitality to Perseus, he was changed into the mountain that still bears his name ; and 
which is so high, that the ancients imagined that the heavens rested upon its summit, 
and consequently, that Atlas supported the wodd on his shoulders. Virgil has this 
idea, where he speaks of " Atlas, whose brawny back supports the skies :" and He- 
siod, verse 783, advances the same notion :— 

" Atlas, so hird necessity ordains, 
Erect, the ponderous vault of stars sustains, 
Not fir from the Hesperides he stands. 
Nor from the load retracts his head or hands." 

From this very ancient and whimsical notion, Atlas is represented by artists, and in 
works of mythology, as an Jd man bearing the world on his shoulder*. Heuce it is, 
that a collection of maps, embracing the whole world, is callad an Atlas. 



HAP V.] LYRA. 121 

His towering crest was glorious to behold ; 

His shoulders and his sides were scaled with gold ; 

Three tongues he brandish'd when he charged his foes; 

His teeth stood jaggy in three dreadful rows. 

The Tynans in the den for water sought, 

And with their urns explored the hollow vault : 

From side to side their empty urns rebound, 

And rouse the sleeping serpent with their sound. 

Straight he bestirs him, and is seen to rise ; 

And how with dreadful hissings fills the skies. 

And darts his forky tongues, and rolls his glaring eyes. 

The Tyrians drop their vessels in the fright, 

All pale and trembling at the hideous sight. 

Spire above spire uprear'd in air he stood, 

And gazing round him. overlook'd the wood : 

Then floating on the ground in circles roll'd ; 

Then leap'd upon them in a mighty fold. 

All their endeavors and their hopes are vain ; 

Some die entangled in the winding train ; 

Some are devour'd, or feel a loathsome death. 

Swollen up with blasts of pestilential breath." 

Cadmus, beholding such a scene, boldly resolved to avenge, or to share their 
fate. He therefore attacked the monster with slings and arrows, and, with the 
assistance of Minerva, slew him. He then plucked out his teeth, and sowed 
them, at the command of Pallas, in a plain, when they suddenly sprung up into 
armed men. 

' Pallas adest : motEcque jubet supponere terrse 

Viperos dentes, populi increments futuri. 

Paret : et. ut presso sulcum pate ecit aratro, 

Spargit humi jusses, mortalia semina dentes. 

hide (fide majus) glebee csepere moveri : 

Primaque de sulcis acies apparuit hast<e 

Te-nnina mox capitum picto nutantia cono : 

Existunt : crescitque seges clvpeata virorum." 

Ovid's Met. lib. ,ii. v. 102. 
11 He sows the teeth at Pallas's command, 

And flings the future people from his hand. 

The clods grow warm, and crumble where he sows; 

And now the pointed spears advance in rows ; 

Now noijding plumes appear, and shining crests, 

Now the broad shoulders and the rising breasts; 

O'er all the field the breathing harvest swarms, 

A growing host ! a crop of men and arms !" 

Entertaining worse apprehension from'the direful offspring than he had done 
from the dragon himself, he was about to fly, when they fell upon each other, 
and were allslain in one promiscuous carnage, except five, who assisted Cadmus 
to build the city of Boeotia 



LYRA. 

The Harp. — This constellation is distinguished by one of 
the most brilliant stars in the northern hemisphere. It is sit- 
uated directly south of the first coil of Draco, between the 
Swan on the east, and Hercules on the west; and when on 
the meridian, is almost directly overhead. 

It contains twenty-one stars, including one of the 1st mag- 
nitude, two of the 3d, and as many of the 4th. 

By what is the constellation of the Harp distinguished ? Where is it situated ? V hat 
are the number and magnitude of its stars ? 
11 



122 PICTURE OF THE HEAVENS. [AUG. 

"There Lyra, for the brightness of her stars, 
More than tiieir number, eminent ; thrice seven 
She counts, and one of these illuminates 
The heavens far around, blazing imperial 
In the first order." 

This star of :i the first order, blazing with imperial " luster, 
is called Vega, and sometimes Wega ; but more frequently 
it is called Lyra, after the name of the constellation. 

There is no possibility of mistaking this star for any other. 
It is situated 14|° S. E. of Etanin, and about 30° N. N. E. of 
Ras Alhague and Ras Algethi. It may be certainly known 
by means of two small, yet conspicuous stars, of the 5th mag- 
nitude, situated about 2° apart, on the east of it, and making 
with it a beautiful little triangle, with the angular point at 
Lyra. 

The northernmost of these two small stars is marked Epsilon, and the south- 
ern one. Zela. About 2° S. E. of Zeta. and in a line with Lyra, is a star of the 
4th magnitude, marked Delta, in the middle of the Harp; and 4° or 5° S. of 
Delta, are two stars of the 3d magnitude, about 2° apart, in the garland of the 
Harp, forming another triangle, whose vertex is in Delia. The star on the cast 
is marked Gamma; that on the west, Beia. If a line be drawn from Etanin 
through Lyra, and produced 6° farther, it will reach Beta. 

This is a variable star, changing from the 3d to nearly the 5th magnitude in the 
space of a week ; it is supposed to have spots on its surface, and to turn on its 
axis, like our sun. 

Gamma comes to the meridian 21 minutes after Lyra, and precisely at the 
same moment with Epsilon, in the tail of the Eagle, 17i° S. of it. 

The declination of Lyra is about 381° N. ; consequently 
when on the meridian, it is but 2° S. of the zenith of Hart- 
ford. It culminates at 9 o'clock, about the 13th of August. 
It is as favorably situated to an observatory at Washington, 
as Rastaben is to those in the vicinity of London. 

Its surpassing brightness has attracted the admiration of 
astronomers in all age^. Manilius, who wrote in the age of 
Augustus, thus alludes to it: — 

" One, placed in front above the rest, displays. 
A vigorous light and darts surprising rays.'" 

Astronomicon, B. i. p. 15. 

History. — It is generally asserted that this is the celestial Lyre which Apollo 
or Mercury gave to Orpheus, and upon which lie played with Mich ;. 
hand, that even the most rapid rivers ceased to flow, the w ill beasts of the forest 
forgot their wildness, and the mountains came to listen to lis goi g. 

Of ail the nymphs who used lo listen io his .-< n ;, Euryi ice was the oily one 
who made adeep impression on the musician, and their nuptials were ci li 
Their happiness, however, was short. Arisiaeus became enamored of Euiydice, 
and as she fled from her pursuer, a serpent, lurking in the grass. hit her foot, 
and she died of the wound. Orpheus resolved to recover her. or perish in the 
attempt. With his lyre in his hand, he entered the internal regi >us and gained 
admission to Pluto." The king of hell was charmed with his s rains, tlie w eo. 

Whnt is the name of the principal star ? Describe its position. By what means may 
inly know n ? Wiatt air tint name- of tne. tic > x/ua- 1 stars fn 
tiie triangle! Describe the star in t if. mi Lie of the Harp, a 
forms another triangle, llmv arc inc. star* in the !•■ 

map! How else may Beta be pointed out ' What is there remarkable in the appear- 
ance of tin's star! When >"■>- Gamiha on the meridian! What is the decliualMM of 
Lyra; When does it culminate ! What ancient poet mentions it? « 



MAP V.] LYRA. 123 

of Ixion stopped, the stone of Sisyphus stood still, Tantalus forgot his thirst, and 
even the furies relented. 

Pluto and Proserpine were moved, and consented to restore him Eurydice, 
provided lie forbore looking behind him till he had come to the exfremest bor- 
ders of their dark dominions. The condition was accepted, and Orpheus was 
already in sight of the upper regions of the air, when he forgot, and turned back 
to look" at his long-lost Eurydice. lie saw her, but she instantly vanished from 
his sight. He attempted again to follow her. but was refused admission. 

From this time Orpheus separated himself from the society of mankind, which 
so offended the Thracian women, it is said, that they tore his body to pieces, and 
threw his head into the Hebrus, still articulating the' words Eurydice ! Eurydice ! 
as it was carried down the stream into the ^Eizean sea. Orpheus was one of the 
Argonauts, of which celebrated expedition he wrote a poetical account, which is 
still extant. After his death, he received divine honors, and his lyre became one 
of the constellations. 

This fable, or allegory, designed merely to represent the power of music in the 
hands of the great master of the science, is similarly described by three of the 
most renowned Latin poets. Virgil, in the fourth book of his Georgics, thus 
describes the effect of the lyre :— 

"E'en to the dark dominions of the night 
He took his way. through forests void of light, 
And dared amid the trembling ghosts to sing, 
And stood before the inexorable king. 
The infernal troops like passing shadows glide, 
And listening, crowd the sweet musician's side ; 
Men, matrons, children, and the unmarried maid, 
The mighty hero's more majestic shade, 
And youth, on funeral piles before their parents laid 
E'en from the depths of hell the damn'd advance; 
The infernal mansions, nodding, seem to dance; 
The gaping three-mouth'd dog forgets to snarl ; 
The furies hearken, and their snakes uncurl ; 
Ixion seems no more his pain to feel, 
But leans attentive on his standing wheel. 
All dangers past, at length the lovely bride 
In safety goes, with her melodious guide." 

Pythagoras and his followers represent Apollo playing upon a harp of seven 
strinas, by which is meant (as appears from Pliny, b. ii. c. 22, Macrobius i. c. 
19, and Censorinus c. ii.). thesun in conjunction with the seven planets ; for they 
made him the leader of that septenary chorus, and the moderator of nature, and 
thought that by his attractive force he acted upon the planets in the harmonical 
ratio of tiieir distances. 

The doctrine of celestial harmony, by which was meant the music of the 
spheres, was common to all the nations of the East. To this divine music Euri- 
pides beautifully alludes:— "Thee I invoke, thou self-created Being, who gave 
birth to Nature, and whom light and darkness, and the whole train of globes 
encircle with eternal music." — So also Shakspeare : — 

" Look, how the floor of heaven 

Is thick inlaid with patines of bright gold ; 

There's not the smallest orb which thou behold'st, 

But in his motion like an angel sings, 

Si ill quiring to the young-eyed cherubim : 

Such harmony is in immortal souls ; 

Bat, while this muddy vesture of decay 

Doth grossly close it in, we cannot hear it." 

The lyre was a famous stringed instrument, much used amone the ancients, 
said to have been invented by Mercury about the year of the world 2000; though 
*ome ascribe the invention to Jubal. (Genesis iv. 21.) It is universally allowed, 
that the lyre was the first instrument of the string kind ever used in Greece. 
The different, lyres, at various periods of time, had from four to eighteen strings 
each. The modern lyre is the Welsh harp. The lyre, among painters, is an 
attribute of Apollo and the Muses. 

All poetry, it lias been conjectured, was in its origin lyric: that is, adapted to 
recitation or song, with the accompaniment of music, and distinguished by the 



124 PICTURE OF THE HEAVENS. [AUG. 

utmost boldness of thought and expression ; being at first employed in celebrat- 
ing the praises of gods and heroes. 

Lesbos was the principal seat of tbe Lyric Muse ; and Terpander, a native of 
this island, who flourished about 650 years B. C.« is one of the earliest of the 
lyric poets whose name we find on record. Sappho, whose misfortunes have 
united with her talents to render her name memorable, was born at Mitylene, the 
chief city of Lesbos. She was reckoned a tenth muse, and placed without con- 
troversy"at the head of the female writers in Greece. But Pindar, a native of 
Thebes, who flourished about 500 years B. C, is styled the prince of lyric poets. 
To him his fellow-citizens erected a monument ; and when the Lacedemonians 
ravaged Bceotia, and burnt the capital, the following words were written upon 
the door of the poet : Forbear to b-urn this house It was the dwelling 
of Pindar. 



SAGITTARIUS. 

The Archer. — This is the ninth sign and the tenth con- 
stellation of the Zodiac. It is situated next east of Scorpio, 
with a mean declination of 35° S. or 12° below the ecliptic. 

The sun enters this sign on the 22d of November, but does 
not reach the constellation before the 7th of December. 

It occupies a considerable space in the southern hemisphere, 
and contains a number of subordinate, though very conspicu- 
ous stars. The whole number of its visible stars is sixty- 
nine, including five of the 3d magnitude, and ten of the 4th. 

It may be readily distinguished by means of five stars of 
the 3d and 4th magnitudes, forming a figure resembling a 
little, short, straight-handled dipper, turned nearly bottom 
upward, with the handle to the west, familiarly called the 
Milk- Dipper, because it is partly in the Milky- Way. 

This little figure is so conspicuous that it cannot easily be 
mistaken. It is situated about 33° E. of An tares, and comes 
to the meridian a few minutes after Lyra, on the 17th of Au- 
gust. Of the four stars forming the bowl of the Dipper, the 
two upper ones are only 3° apart, and the lower ones 5°. 

The two smaller stars forming the handle, and extending westerly about 4M, 
and the easternmost one in the bowl of the Dipper, arc ail of the 4th magnitude. 
The star in the end of the handle, is marked Lamb i a. and is placed in the bow 
of Sagittarius, just within the Milky-Way. Lambda may otherwise be known 
by its being nearly in a line with two other stars about 4/,° apart, extending to- 
ward the S E. It is also equidistant from Phi and Delia, with which it makes 
a handsome triangle, with the vertex in Lambda. About 5° above Lambda, and 
a little to the west, are two stars close together, in the end of the bow, the bright- 
est of which is of the 4th magnitude, and marked Ma. This star serves to point 
out the winter solstice, being about 2° N. of the tropic of Capricorn, and less 
than one degree east of the solstitial colure. 

If a line be drawn from Sigma through Phi, and produced about 6° farther to 
the west, it will point out Delia, and produced about 3° from Delta, it will point 

What is the order in the Zodiac of Sagittarius? How is it situated ? When doe* 
the sun appear to enter this constellation? What are its extent and appearance? 
What are the number and magnitude of its stars ? How may it be readily distinguish- 
ed .' What is this figure called, and why ? Where is this figure to be found, and when 
is it on the meridian ? How lar apart are the two upper stars in the bowl of the Dip 
per? How far apart are the two lower ones? Describe the stars in the handle. De- 
scribe the position of Lambda. I J mo may Lambda be otherwise knoton? With what 
other start does it form a handsome triangle ? Describe the position of Ma. Umo may 
Delta and Gamma be pointed out ? 



MAP V.] AQUILA ET ANTINOUS. 125 

out Gamma; stars of the 3d magnitude, in the arrow. The latter is in the point 
of the arrow, and may be known by means of a small star just above it, on the 
right. This star is so nearly on the same meridian with Etanin, in the head of 
Draco, that it culminates only two minutes after it. 

A few other conspicuous stars in this constellation, forming a variety of geomet- 
rical figures, may be easily traced from the map. 

History. — This constellation, it is said, commemorates the famous Centaur 
Chiron, son of Philyra and Saturn, who changed himself into a horse, to elude 
the jealous inquiries of his wife Rhea. 

Ciiiron was famous for his knowledge of music, medicine and shootiug. He 
taught mankind the use of plants and medicinal herbs ; and instructed, in all the 
polite arts, the greatest heroes of his age. He taught ^Esculapius physic, 
Apollo music, and Hercules astronomy ; and was tutor to Achilles, Jason, and 
jEneas. According to Ovid, he was slain by Hercules, at the river Evenus, for 
offering indignity to his newly married bride. 

' ; Thou monster double shap'd, my right set free — 
Swift as his words, the fatal arrow flew : 
The Centaur's back admits the feather'd wood, 
And through his breast the barbed weapon stood ; 
Which, when in anguish, through the flesh he tore, 
From both the wounds gush'd forth the spumy gore." 
The arrow which Hercules thus sped at the Centaur, having been dipped in 
the blood of the Lernsean Hydra, rendered the wound incurable, even by the 
father of medicine himself, and he begged Jupiter to deprive him of immortality, 
if thus he might escape his excruciating pains. Jupiter granted his request, and 
translated him to a place among the constellations. 

" Midst golden stars he stands refulgent now, 
And thrusts the scorpion with his bended bow." 
This is the Grecian account of Sagittarius ; but as this constellation appears on 
the ancient zodiacs of Egypt, Dendera, Esne, and India, it seems conclusive that 
the Greeks only borrowed the figure, while they invented the fable. This is 
known to be true with respect to very many of the ancient constellations. Hence 
the jargon of the conflicting accounts which have descended to us. 



AGIUILA ET ANTINOUS. 

The Eagle and Antinous. — This double constellation is 
situated directly south of the Fox and Goose, and between 
Taurus Poniatowski on the west, and the Dolphin on the 
east. It contains seventy-one stars, including one of the 1st 
magnitude, nine of the 3d. and seven of the 4th. It may be 
readily distinguished by the position and superior brilliancy 
of its principal star. 

Altair, the principal star in the Eagle, is of the 1st, or be- 
tween the 1st and 2d magnitudes. It is situated about 14° S. 
W. of the Dolphin. It may be known by its being the largest 
and middle one of the three bright stars which are arranged 
in a line bearing N. W. and S. E. The stars on each side 
of Altair are of the 3d magnitude, and distant from it about 
2°. This row of stars very much resembles that in the 
Guards of the Lesser Bear. 

How is Gamma situated tcith respect to Etaninl In what part of the heavens is the 
Eagle situated ? What are the number and magnitude of its stars ? Ht>w is it distin- 
guished i Describe its principal star. How may it be kn wn ? What is the magni- 
tude of the stare on each side of Altair? How far distant from it are they 1 What row 
of stars does this row resemble 1 

11* 



126 PICTURE OF THE HEAVENS [AUG. 

Altair is one of the stars from which the moon's distance 
is taken for computing longitude at sea. Its mean declina- 
tion is nearly 8i° N., and when on the meridian, it occupies 
nearly the same place in the heavens that the sun does at 
noon on the 12th day of April. It culminates about 6 mi- 
nutes before 9 o'clock, on the last day of August. It rises 
acronically about the beginning of June. 

Ovid alludes to the rising of this constellation ; or, more probably, to that of the 
principal star, Altair :— 

" Now view the skies. 

And you'll behold Jove's hook'd-bill bird arise.'' 

Massey's Fasti. 

■ " Among thy splendid group 

One dubious whether of ihe Second rank, 
Or to the First entitled ; but whose claim 
Seems to deserve the First." 

Eudosia. 
The northernmost star in the line, next above Altair. is called Tarazed. In 
the wing of the Eaile, there is another row composed of three stars, situated 4° 
or 5° apart, extending down toward the south-west ; the middle one in this line 
is the smallest, being only of the 4th magnitude ; the next is of the 3d magni- 
tude, marked Delta, and situated 8° S. W. of Altair. 

As you proceed from Delta, there is another line of three stars of the 3d mag- 
nitude, between 5° and 6° apart, extending southerly, but curving a little to the 
west, which mark the youth Antinous. The northern wing of the Eagle is net 
distinguished by any conspicuous stars. 

Zeta and Epsilon, of the 3d magnitude, situated in the tail of the Eagle, are 
about 2° apart, and 12° N. W. of Altair. The last one in the tail, marked Epsi- 
lon. is on the same meridian, and culminates the same moment with Gamma, in 
the Harp. 

From Epsilon, in the tail of the Eagle, to Theta, in the wrist of Antinous. may 
be traced a Ions line of stars, chiefly of the 3d magnitude, whose letter names 
are Theta, Eta. Mu, Zeta, and Epsilon. The direction of this line is from S. E. 
to N. W., and its length is about 25°. 

Eta is remarkable for its changeable appearance. Its greatest brightness con- 
tinues but 40 hours ; it then gradually diminishes for 66 hours when its luster 
remains stationary for 30 hours. It then waxes brighter and brighter, until it 
appears again as a star of the 3d magnitude. 

From these phenomena, it is inferred that it not only has spots on its surface, 
like our sun, but that it also turns on its axis. 

Similar phenomena are observable in Algol, Beta, in the Hare, Delta, in Ce- 
pheus, and Omicron, in the Whale, and many others. 



— " Aquila the next, 



Divides the ether with her ardent wing: 
Beneath the Swan nor far from Pegasus, 
Poetic Eagle." 

History. — Aquila, or the Eagle, is aconstellation usually joined with Antinous. 
Aquila is supposed to have been Merops, a king of the island of Cos. in the Ar- 
chipelago, and the husband of Clymene, the mother of Phaeton ; this monarch 
having been transformed into an eagle, and placed among the constellations. 
Some have imagined that Aquila was the eagle whose form Jupiter assumed 
when he carried away Ganymede ; others, that it represents the eagle which 
brought nectar to Jupiter while he lay concealed in the cave at Crete, to avoid 

Of what importance is this star at sea? What is its declination ? What place does 
it occupy in the heavens when on the meridian, and when does it culminate ? When 
does it rise acronically ? Describe the position of Tarazed. Describe the roio of start 
in the wing of the Eagle. Describe the row of stars which mark the youth Antinous. 
What stars in the northern wins ? Describe Zeta and Epsilon. When is Epsilon on 
the meridian ? What long line of stars terminates at Epsilon » What are the direction 
and extent of this line ? Describe the remarkable appearance of Eta. What is in- 
ferred from tliese plienomena ? 



MAP V.] DELPHINUS. 127 

die fury of his father, Saturn. Some of the ancient poets say, that this is the 
eagle which furnished Jupiter with weapons in his war with the giants •— 

H The towering Eagle next doth boldly soar, 
As if the thunder in his claws he bore ; 
He's worthy Jove, since he, a bird, supplies 
The heaven* with sacred bolts, and arms the skies." 

Manilius. 
The eagle is justly styled the " sovereign of birds." since he is the largest, 
Wrongest, and swiftest of all the feathered tribe that live by prey. Homer calls 
ihe eagle, " the strong sovereign of the plumy race ;" Horace styles him— 

" The royal bird, to whom the king of heaven 
The empire of the feathered race has given :" 

And Milton denominates the eagle the '" Bird of Jove." lis 6ight is quick* 
strong and piercing, to a proverb : Job xxix. 28, <fcc. 

" Though strong the hawk, though practiced well to fly, 
An eagle drops her in the lower sky ; 
An eagle when deserting human sight, 
She seeks the sun in her unwearied flight ; 
Did thy command her yellow pinion lift 
So high in air, and set her on the clift 
Where far above thy world she dwells alone, 
And proudly makes' the strength of rocks her own ; 
Thence wide o'er nature takes her dread survey, 
And with a glance predestinates her prey ? 
She feasts her young with blood ; and hovering over 
The unslaughtered host, enjoys the promised gore." 

ANTINOUS. 

Antinous is a part of the constellation Aquila, and was invented by Tyche 
Brahe. Antinous was a youth of Bithynia, in Asia Minor. So greatly was his 
death lamented by the emperor Adrian, that he erected a temple to his memory, 
and built in honor of him a splendid city, on the banks of the Nile, the ruins of 
which are still visited by travelers with much interest. 



CHAPTER XL 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE MERIDIAN IN SEPTEMBER. 

DELPHINUS. 

The Dolphin. — This beautiful little cluster of stars is sit- 
uated 13° or 14° N. E. of the Eagle. It consists of eighteen 
stars, including four of the 3d magnitude, but none larger. 
It is easily distinguished from all others, by means of the 
four principal stars in the head, which are so arranged as to 
form the figure of a diamond, pointing N. E. and S. W. To 
many, this cluster is known by the name of JoVs Coffin ; 
but from whom, or from what fancy, it first obtained this 
appellation, is not known. 

Where is the constellation Delphinns situated ? What are the number and magni- 
tude of its stars ? How is this constellation distinguished from nil others ! What sin- 
gular name is sometimes given to this cluster, and whence was it derived ? 



128 PICTURE OF THE HEAVENS. [SEPT. 

There is another star of the 3d magnitude, situated in the 
body of the Dolphin, about 3° S. W. of the Diamond, and 
marked Epsilon. The other four are marked Alpha, Beta, 
Gamma, Delta. Between these are several smaller stars, 
too small to be seen in presence of the moon. 

The mean declination of the Dolphin is about 15° N. It 
comes to the meridian the same moment with Deneb Cyg- 
ni, and about 50 minutes after Aitair, on the 16th of Sep 
tember. 

" Thee I behold, majestic Ct/gnus, 
On the marge dancing of the heavenly sea, 
Arion's friend ; eighteen thy stars appear — 
One telescopic." 
History.— The Dolphin, accordin? to some mythologists, was made a constel- 
lation by Neptune, because one of these beautiful fishes had persuaded the god- 
dess Amphitrite, who had made a vow of perpetual celibacy, to become the wife 
of that deity ; but others maintain, that it is the dolphin which preserved the fa- 
mous lyric poet and musician Arion, who was a native of Lesbos, an island in the 
Archipelago. 

He went to Italy with Periander, tyrant of Corinth, where he obtained im- 
mense riches by his profession. Wishing to revisit his native country, the sailors 
of the ship in which" he embarked resolved to murder him, and get possession 
of his wealth. Seeing them immovable in their resolution, Arion begged per- 
mission to play a tune upon his lute before he should be put to death. The mel- 
ody of the instrument attracted a number of dolphins around the ship ; he im- 
mediately precipitated himself into the sea ; when one of them, it is asserted, 
xarried him safe on his back to Teenarus, a promontory of Laconia. in Pelopon- 
nesus ; whence he hastened to the court of Periander, who ordered all the sail 
ors to be crucified at their return. 

" But, (past belief.) a dolphin's arched back 
Preserved Arion from his destined wrack ; 
Secure he sits, and with harmonious strains 
Requites his bearer for his friendly pains." 

When the famous poet Hesiod was murdered in Naupactum, a city of jEtolia, 
in Greece, and his body thrown into the sea, some dolphins, it is said, brought 
back the floating corpse to the shore, which was immediately recognized by his 
friends; and the assassins being afterward discovered by the dogs of the de- 
parted bard, were put to death by immersion in the same sea. 

Taras, said by some to have been the founder of Tarentum. now Tarento, in 
the south of Italy, was saved from shipwreck by a dolphin ; and the inhabitants 
of that city preserved the memory of this extraordinary event on their coin. 

The natural shape of the dolphin, however, is not incurvated, so that one 
might ride upon its back, as the poets imagined, but almost straight. When it is 
first taken from the water, it exhibits a variety of exquisitely beautiful but eva- 
nescent tints of color, that pass in succession over its body until it dies. They are 
an extremely swift-swimming fish, and are capable of living a long time out of 
water ; in fact, they seem to delight to gambol, and leap out of their native ele- 
ment. 

" Upon the swelling waves the dolphins show 
Their bending backs; then swiftly darting go. 
And in a thousand wreaths their bodies show." 



CYGNUS. 

The Swan — This remarkable constellation is situated in 
the Milky- Way, directly E. of Lyra, and nearly on the same 

Mention some other stars in the Dolphin. What is the mean declination of the Dol- 
phin, and when is it on the meridian? In what part of the heavens is the constellation 
Cygnus situated ? 



MAP V.] CYGNUS. 129 

meridian with the Dolphin. It is represented on outspread 
wings, flying down the Milky-Way, toward the south-west. 

The principal stars which mark the wings, the body and 
the bill of Cygnus, are so arranged, as to form a large and 
regular Cross; the upright piece lying along the Milky- 
Way from N. E. to S. W., while the cross piece, represent- 
ing the wings, crosses the other at right angles, from S. E. 
to N. W. 

Aridecl, or Deneb Cygni. in the body 6f the Swan, is a star 
of the second magnitude, 24° E. N. E. of Lyra, and 30° di- 
rectly N. of the Dolphin. It is the most brilliant star in the 
constellation. It is situated at the upper end of the cross, 
and comes to the meridian at 9 o'clock on the 16th of Sep- 
tember. 

Sad'r is a star of the 3d magnitude, 6° S. W. of Deneb, situated exactly in the 
cross, or where the upright piece intersects the cross piece, and is about 20° E. 
of Lyra. 

Delta, the principal star in the west wing, or arm of the cross, is situated N. 
W. of Sad'r. at the distance of little more than 8°, and is of the 3d magnitude. 
Beyond Delta, toward the extremity of the wing, are two smaller stars about 5° 
apart, and inclining a little obliquely to the north; the last of which reaches 
nearly to the first coil of Draco. These stars mark the west wing ; the east wiug 
may be traced by means of stars very similarly situated. 

Gienah is a star of the 3d magnitude, in the 'east wing, just as far east of Sad'r 
in the center of the cross, as Delta is west of it. This row of three equal stars, 
Delta, Sad'r, and Gienah, form the bar of the cross, and are equidistant from 
each other, being about 8° apart. Beyond Gienah on the east, at the distance of 
6° or 7°, there are two other stars of the 3d magnitude ; the last of which marks 
the extremity of the eastern wing. 

The stars in the neck are all too small to be noticed. There is one, however, 
in the beak of the Swan, at the foot of the cross, called Albireo, which is of the 
3d magnitude, and can be seen very plainly. It is about 16° S. W. of Sad'r, and 
about the same distance S. E. of Lyra, with which it makes nearly a right angle. 

'•In the small space between Sad'r and Albireo," says Dr. Herschel, " the stars 
in the Milky-Way seem to be clustering into two separate divisions ; each divi- 
sion containing more than one hundred and sixty-five thousand stars." 

Albireo bears northerly from Altair about 20°. Immediately south and south- 
east of Albireo, may be seen the Fox and Goose ; and about midway between 
Albireo and Altair, there may be traced a line of four or five minute stars, called 
the Arrow; the head of which is on the S. W., and can be distinguished by 
means of two stars situated close together. 

According to the British catalogue, this constellation con- 
tains eighty-one stars, including one of the 1st or 2d mag- 
nitude, six of the 3d, and twelve of the 4th. The author of 
the following beautiful lines says there are one hundred 
and seven. 

" Thee, silver Swan, who, silent, can o'erpass? 
A hundred with seven radiant stars compose 
Thy graceful form : amid the lucid stream 

How is it represented ? What remarkable figure is formed by its principal stare t 
Describe the position and appearance of Arided, or Deneb Cyfrni. When does it culmi- 
nate at 9 o'clock ? Describe the position of Sad'r. Describe Delta. What stars beyond 
Delta:- What stars in the east wing') What staisfonn the bar of the cross) What 
stars beyond Gienah on the east ? Describe the stars in the neck a?id bill of the Swan. 
Hoio is the star in the bill situated with respect to Sad'r and Lyra ) What clusters 
south and south-east of Albireo? What are the number and magnitude of the stars in 
the Swan I 



130 PICTURE OF THE HEAVENS. [SEPT. 

Of the fair Milky-Way distinguished ; one 

Adorns the second order, where she cuts 

The waves that follow in her utmost track ; 

This never hides its fire throughout the night, 

And of the rest, the more conspicuous mark 

Her snowy pinions and refulgent neck." — Eudosia, b. iv. 

Astronomers have discovered three variable stars in the Swan. Chi, situated 
in the neck, between Beta and Sad'r, was first observed 10 vary its briszhtne^s 
in 1686. Its periodical changes of light are now ascertained to be completed in 
405 days. Sad'r is also changeable. Its greatest luster is somewhat less than 
that of" a star of the 3d magnitude, and it gradually diminishes till it reaches that 
of the 6th. Its changes ar#far from being regular, and. from present observa- 
tions, they do not seem to recur till after a period of ten years or more. 

A third variable star was discovered in the head on the 20th of June, 1670, by 
Anthelme. It appeared then to be of the 3d magnitude, but was so far diminished 
in the following October, as to be scarcely visible. In the beginning of April, 
1671, it was again seen, and was rather brighter than at firsL After several 
changes, it disappeared in March, 1672, and has not been observed since. 

These remarkable facts seem to indicate, that there is a brilliant planetary 
system in this constellation, which, in some of its revolutions, becomes visible 
to us. 

History. — Mythologists eive various accounts of the origin of this constella- 
tion. Some suppose it is Orpheus, the celebrated musician, who, on being mur- 
dered by the cruel priestess of Bacchus, was changed into a Swan, and placed 
near his Harp in the heavens. Others suppose it is the swan into which. lupiter 
transformed himself when he deceived Leda, wife of Tyndarus, king of Sparta. 
Some affirm that it was Cycnus, a son of Neptune, who was so completely invul- 
nerable that neither the javelins nor arrows, nor even the blows of Achilles, in 
furious combat, could make any impression. 

" Headlong he leaps from off his lofty car, 
And in close fight on foot renews the war; — 
But on his flesh nor wound nor blood is seen, 
The sword itself is blunted on the skin." 

But when Achilles saw that his darts and blows had no effect on him. he \m- 
mediately threw him on the ground and smothered him. While he was attempt- 
ing to despoil him of his armor, he was suddenly changed into a swan. 
" With eager haste he went to strip the dead ; 

The vanished body from his arms was fled. 

His sea-god sire, to immortalize his fame, 

Had turned it to a bird that bears his name." 
According to Ovid this constellation took its name from Cycnus, a relative of 
Phaeton, who deeply lamented the untimely fate of that youth, and the melan- 
choly end of his sisters, who, standing around his tomb, wept themselves into 
poplars. 

" Cycnus beheld the nymphs transformed, allied 

To their dead brother on the mortal side, 

In friendship and affection nearer bound ; 

He left the cities, and the realms he owned, 

Through pathless fields, and lonely shores to range; 

And woods made thicker by the sisters' change : 

While here, within the dismal gloom alone, 

The melancholy monarch made his moan ; 

His voice was lessened as he tried to speak. 

And issued through a long-extended neck : 

His hair transforms to down, his fingers meet 

In skinny films, and shape his oary feet ; 

From both his sides the wings and feathers break : 

And from his mouth proceeds a blunted beak ; 

All Cycnus now into a swan was turned." — Ovid's Met. b. ii. 

What varinble stars have astronomers discovered in this constellation' Which of 
these was first discovered to be variable in 1686'' In what period are its 'periodical 
changes of light completed ? Describe the appearance of Sad'r. Describe the one dis- 
covered in 1670. What do these remarkable *acts indicate ? 



MAP V.J CAPRICORNUS. 131 

Virgil, also, in the 10th book of his ^Eneid, alludes to the same fable •- 
" For Cycnus loved unhappy Phaeton, 
And sung his loss in poplar groves alone 
Beneath the sister shades to soothe his grief; 
Heaven heard his song, and hasten'd his relief; 
And changed to snowy plumes his hoary hair, 
And wing r d his flight to sing aloft in air." 
Of all the feathered race, there is no bird, perhaps, which makes so beautifu* 
and majestic an appearance as the swan. Almost every poet of eminence has 
taken notice of it. The swan has, probably, in all ages, and in every country 
where taste and elegance have been cultivated, been considered as the emblem 
of poetical dignity, purity, and ease. By the ancients it was consecrated to Apollo 
and the Muses ; they also entertained a notion that this bird foretold its own end, 
and sang more sweetly at the approach of death. 

" She, like the swan 

Expiring, dies in melody." — jEschylus. 
" So on the silver stream, when death is nigh, 
The mournful swan sings its own elegy." — Ovid's Tristi&. 



CAPRICORNUS. 

The Goat. — This is the tenth sign, and eleventh constel- 
lation, in the order of the Zodiac, and is situated south of 
the Dolphin, and next east of Sagittarius. Its mean declina- 
tion is 20° south, and its mean right ascension, 310°. It is 
therefore on the meridian about the 18th of September. It 
is to be observed that the first point of the sign Capricorn, 
not the constellation, marks the southern tropic, or winter 
solstice. The sun, therefore, arrives at this point of its orbit 
the 21st of December, but does not reach the constellation 
Capricorn until the 16th of January. 

The sun, having now attained its utmost declination south, 
after remaining a few days apparently stationary, begins 
once more to retrace its progress northwardly*, affording to 
the wintry latitudes of the north a grateful presage of re- 
turning spring. 

At the period of the winter solstice, the sun is vertical to 
the tropic of Capricorn, and the southern hemisphere enjoys 
the same light and heat which the northern hemisphere en- 
joys on the 2 1st of June, when the sun is vertical to the tro- 
pic of Cancer. It is, at this period, mid-day at the south 
pole, and midnight at the north pole. 

The whole number of stars in this constellation is fifty- 
one ; none of which are very conspicuous. The three larg- 
est are only of the 3d magnitude. There is an equal num-' 
ber of the 4th. 

Where is Capricomus situated ? What are its mean ri^ht ascension and declination' 
When is the main body of the constellation on the meridian? When does the sun en- 
ter the sign-, and when the constellation Capricorn I Does the sun ever extend heyond 
this point into the southern hemisphere ? What is the position ol'the sun with respect 
to the tropic of Capricorn, at. the winter solstice, and what are the seasons in the two 
hemispheres ? What are the number and magnitude of the stars in thia constel- 
lation.! 



132 PICTURE OF THE HEAVENS. [SEPT. 

The head of Capricorn may be recognized by means of 
two stars of the 3d magnitude, situated a little more than 2° 
apart, called Giedi and Dabih. They are 28° from the Dol- 
phin, in a southerly direction. 

Giedi is the most northern star of the two, and is double. 
If a line be drawn from Lyra through Altair, and produced 
about 23° farther, it will point out the head of Capricorn. 
These two stars come to the meridian the 9th of September, 
a few minutes after Sad'r, in Cygni. 

A few other stars of inferior note may be traced out by 
reference to the maps. 

The sign of the Goat was called by the ancient oriental- 
ists the '• Southern gate of the Sun," as Cancer was denom- 
inated the " Northern gate." The ten stars in the sign Ca- 
pricorn, known to the ancients by the name of the " Tower 
of Gad," are probably now in the constellation Aquarius. 

History. — Capricornus is said to be Pan , or Bacchus, who, with some other 
deities were feasting near the banks of the Nile, when suddenly the dreadful 
giant Typhon came upon them, and compelled them all to assume a different 
shape, in order to escape his fury. Ovid relates, 

'. : How Typhon, from the conquer'd skies, pursued 

Their routed godheads to the seven-mouth'd flood : 

Forced every god, (his fury to escape,) 

Some beastly form to take, or earthly shape. 

Jove (sings the bard) was chang'd into a ram, 

From whence the horns of Libyan Ammon came ; 

Bnrchus a goat ; Apollo was a crow ; 

Phoebe a cat ; the wife of Jove a cow, 

Whose hue was whiter than the falling snow ; 

Mercury to a nasty ibis turned — 

While Venus from a fish protection craves, 

And once more plunges in her native waves." 

On this occasion it is further related that Bacchus, or Pan, led the way ana 
plunged into the Nile, and that the part of his body which was under the water 
assumed the form of a fish, and the other part that of a goat; and that to preserve 
the memory of this frolic, Jupiter made him into a constellation, in his metamor- 
phosed shape. 

Some say thai this constellation was the goat Amalthea, who supported the in- 
fant Jupiter with her milk. To reward her kindness, the father of the gods 
placed her among the constellations, and gave one of her horns to the nymphs 
who had taken care of him in his infantile years. This gift was ever after called 
the horn of plenty ; as it possessed the virtue of imparting to the holder what- 
ever she desired.* 

The real sense of this fable, divested of poetical embellishment, appears to be 
this ; that in Crete, some say in Libya, there was a small territory shaped very 
much like a bullock's horn, and exceedingly fertile, which the king presented to 
his daughter Amalthea, whom the poets feigned to have been Jupiter's nurse. 

" The bounteous Pan," as he is styled by Milton, was the god of rural scffuery, 
shepherds, and huntsmen. Virgil thus addresses him : — 

* On this account the Latin term Cornucopia, denotes plenty, or abundance of good 
things. The word Amalthea, when used figuratively, has also the same meaning. 

How may it be recognized ? How are Giedi and Dabih situated with respect to the 
Dolphin? How are these two stars distinguished from each other, and what is their 
position in respect to the Eagle? When are they on our meridian? What were the 
signs Capricorn and Cancer originally called ? Where sire the ten stars, known to the 
ancients by the name of tha " Tower of Uad," now to be found ? 



MAP II. J PEGASUS. 133 

6 And thou, the shepherd's tutelary sod, 
Leave, for a while, O Fan ! thy loved abode." * 
The name of Pan is derived from a Greek word signifying all things ; and ho 
was often considered as thegreat principle of vegetable and animal Jiie. He 
resided chiefly in Arcadia, in woods and the most rugged mountains. As Pan 
usually terrified the inhabitants of the adjacent country, even when he was no 
where to be seen, that kind of fear which often seizes men, and which is only 
ideal or imaginary, has received from him the name of Panic. 



CHAPTER Xll. 

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE 
ON THE' MERIDIAN IN OCTOBER. 

PEGASUS. 

The Flying Horse — This constellation is represented in 
an inverted posture, with wings. It occupies a large space 
in the heavens. beLween the Swan, the Dolphin and the Ea- 
gle, on the west, and the Northern Fish and Andromeda, on 
the east. Its mean right ascension is 340°, or it is situated 
20° W. of the prime meridian. It extends from the equi- 
noctial N. 35°. Its mean length E. and W. is about 40°, 
and it is six weeks in passing our meridian, viz. from the 1st 
of October to the 10th of November. 

We see but a part of Pegasus, the rest of the animal be- 
ing, as the poets imagined, hid in the clouds. 

It is readily distinguished from all other constellations by- 
means of four remarkable stars, about J5° apart, forming the 
figure of a square, called the Square of Pegasus. The two 
western stars in this square come to the meridian about the 
23d of October, and are 13° apart. The northern one, which 
is the brightest of three triangular stars in the martingale, is 
of the 2d magnitude, and is called Scheat. Its declination is 
2G|° N. Markab, also of the 2d magnitude, situated in the 
bead of the wing, is 13° S. of Scheat, and passes the meri- 
dian II minutes after it. 



" Now, sacred Pules, in a lofty strain, 
I sing the rural honors of thy reign.' 
The shepherds offered to thi3 godiless milk and honey, to gain her protection over 
their llo-ks. Sue is repiesented as an old womm. ami was worshiped with ^-reat 
solemnity at Rome. Her festivals which were called Palilia, were celebrated on tho 
2oth of April, the nay on which Romulus laid tne foundations of the city. 

How is Pegasus represented.' What space and position does it occupy in th- he;\ 
»eus ? What are the distance and direction of its center from the prime meridian? 
Whut are its mean length and breadth? How long i- it in pa-sin- our meridian ' 
When does it pass the meridian? How is this constellation distinguished from ail 
others ? Desc.-ibtt the two stirs which form the west side of the square. 

12 



■ 



134 PICTURE OF THE HEAVENS. [OCT. 

The two stars which form the eastern side of the square, 
come to the meridian about an hour after those in the western. 
The northern one has already been described as Alpheratz 
in the head of Andromeda, but it also belongs to this constel- 
lation, and is 14° E. of Scheat. 14° S. of Alpheratz, is Al- 
genib, the last star in the wing, situated 16i° E. of Markab. 

Algenih in Pegasus, Alpheratz in Andromeda, and Caph in Cassiopeia art 
situated on the prime meridian, and point out its direction through the pole. For 
this reason, they are sometimes called the three guides. They form an arc of • 
that great circle in the heavens from which the distances of all the heavenly 
bodies are measured. It is an arc of the equinoctial colure which passes through 
the vernal equinox, and which the sun crosses about the 21st of March. It is, in 
astronomy, what the meridian of Greenwich is in geography. If the sun, or a 
planet, or a star, be said to have so many degrees of right ascension, it means 
that the sun or planet has ascended so many degrees from this prime meridian 

Enif, sometimes called Enir, is a star of the 3d magnitude in the nose of Pe 
gasus, about 20° W. S. W. of Markab. and half-way between it and the Dolphin. 
About half of the distance from Markab toward Enif, but a little to the S., there is 
a star of the 3d magnitude situated in the neck, whose letter name is Zeta. The 
loose cluster directly S. of the line joining Enif and Zeta. forms the head of 
Pegasus. 

In this constellation there are eighty-nine stars visible to 
the naked eye, of which three are of the second magnitude 
and three of the third. 

History.— This, according to fable, is the celebrated horse which sprum from 
the blood of Medusa, after Perseus had cut off her head. He received his name 
according to Hesiod, from his being born near the sources {^nyn, Pege) of the 
ocean. According to Ovid, he fixed his residence on Mount Helicon, where by 
striking the earth with his foot, he raised the fabled fountain called Hippocrene. 
He became the favorite of the Muses ; and being tamed by Neptune or Minerva, 
he was given to Bellerophon. son of Glaueus, king of Ephyre. to aid him in con- 
quering the Chimaera, a hideous monster that continually vomited flames. This 
monster hud three heads, that of a lion, a goat, and a dragon. The lore parts of 
its body were those of a lion, the middle those of a goat, and the hinder those of 
the dragon. It lived in Lycia, of which the top. on account of its desolate wilder- 
ness, was the resort of lions, the middle, which was fruitful, was covered with 
goats, and at the bottom, the marshy ground abouuded with serpents. Bellero- 
phon was the first who made his habitation upon it. 

Plutarch thinks the Chimaera was the captain of some pirates who adorned 
their ship with the images of a lion, a goat, and a dragon. 

After the destruction of this monster" Bellerophon attempted to fly up to heaven 
upon Pegasus ; but Jupiter was so displeased at this presumption, that he sent 
in insect to sting the horse, which occasioned the melancholy tall of Inc. rider. 
Bellerophon fell to the earth, and Pegasus continued his flight up to heaven, and 
was placed by Jupiter among the constellations. 

'• Now heav'n his further wand'ring flight confines, 
Where, splendid with his num'rous stars, he shines. 

Ovid's Fasti. 



EQUULUS, VEL EQUI SECTIO. 

The Little Horse, or the Horse's Head. — This Aster- 
ism, or small cluster of stars, is situated about 7° AV . of 
Enil" in the head of Pegasus, and about halt-way between it 

Describe the two on me east side. "What is the name of the star in the N. E corner 
of the square? In the S. E. corner? In the S. \V. corner? In the \. \V. corner? 
Describe liup'jSWon and nucgnitudc of Enif. What is the whole number of stars in 
Pegasiw ? What is the maguitude of the i rincipal ones ? Describe the situatiou ofthe 

Little Horse. 



MAP II.] AQUARIUS. 135 

and the Dolphin. It is on the meridian at 8 o'clock, on the 
11th of October. It contains ten stars, of which the four 
principal are only of the 4th magnitude. These may be 
readily distinguished by means of the long irregular square 
which they form. The two in the nose are much nearer to- 
gether than the two in the eyes; the former being 1° apart, 
and the latter 2i°. Those in the nose are uppermost, being 
4° N. of those in the eyes. This figure also is in an inverted 
position. These four stars are situated 10° or 12° S. E. of 
the diamond in the Dolphin's head. Both of these clusters 
are noticeable on account of their figure rather than their 
brilliancy. 

History. — This constellation is supposed to be the brother of Pegasus, named 
Ceteris, given by Mercury to Castor, who was so celebrated for his skill in the 
management of horses; others take him to be the celebrated horse which Nep- 
tune struck out of the earth with his trident, when he disputed with Minerva for 
superiority. The head only of Celeris is visible, and this, also, is represented in 
an inverted position. 

AQUARIUS. 

The Water-Bearer. — This constellation is represented 
by the figure of a man, pouring out water from an urn. It 
is situated in the Zodiac, immediately S. of the equinoctial, 
and bounded by the Little Horse, Pegasus, and the Western 
Fish on the N., the Whale on the E., the Southern Fish on 
the S. and the Goat on the W. It is now the 12th in order, 
or last of the Zodiacal constellations; and is the name of the 
11th sign in the ecliptic. Its mean declination is 14° S., and 
its mean right ascension 335°, or 22 hours, 20 min.; it being 
1 hour and 40 min. W. of the equinoctial colure ; its center 
is, therefore', on the meridian the 15th of October. 

It contains one hundred and eight stars ; of which the fonr 
largest are all of the 3d magnitude. 

>' His head, his shoulders, and his lucid breast, 
Glisten with stars; and where his urn inclines, 
Rivers of light brighten the watery track." 

The north-eastern limit of Aquarius may be readily dis- 
tinguished by means of four stars of the 4th magnitude, in 
the hand and handle of the urn. so placed as to form the let- 
ter Y, very plainly to be seen, 15° S. E. of Enif, or 18° S. 
S. W. of Markab. in Pegasus ; making with the two latter 
nearly a right angle. 

"When is it on the meridian ? What is the whole number of its stars ? What is the 
magnitude of the principal ones? How may the principal stars be distinguished ? 
Haw are the two in the nose distinguished fiom the two in the eyes? What are their 
distance and direction t'rom the Dolphin i On what account are these clusters notice- 
able. • How is Aquarius represented? Where is it situated? What is its present order 
among the constellations of the Zodiac? What are Its right ascension and declination' 1 
What is the whole ii'inilx r of its stars i What is the magnitude of the principal ones' 
How may the N. E. limit of Aquarius be readily distinguished ? What are the distance 
and direction of this letter Y from Markab and Enif! in Pegasus? 



136 PICTURE OF THE HEAVENS. [ OCT. 

About 4i° W. of this figure is El Melik, a star of the 3d magnitude,' in the E. 
shoulder, and the principal one in this constellation. 10° S. W. of El Melik, is 
another star of the same magnitude, situated in the W. shoulder, called Sad es 
Sand. _ _ 

Ancha, of the 4th magnitude, is in the right side, 8" S. of El Melik. 9° E. of 
Ancha, is another star of the 4th magnitude, whose letter name is Lambda. 

Scheat. of the 3d magnitude, lying below the knee, is situated 8J° S. of Lambda ; 
and 14° S. of Scheat, the brilliant star Fomalhaut,* of between the 1st and EJd 
magnitudes, terminates the cascade in the mouth of the Southern Fish. This 
star is common to both these constellations, and is one of those from which the 
lunar distance is computed for ascertaining the longitude at sea. It culminates 
at 9 o'clock on the 22d of October. 

Fomalhaut,* Deneb Kaitos, and Alpha in the head of the Phoenix, make a large 
triangle, whose vertex is in Deneb Kaitos. Those two stars of the 4th magnitude, 
situated 4° S. of Sad es Saud, aud nearly the same distance from Ancha, are in 
the tail of Capricorn. They are about 2° apart. The western one is called 
Deneb Algedi. 

The rest of the stars in the cascade are quite small ; they may be traced from 
the letter Y, in the urn, in a south-easterly direction toward the tail of Cetus, 
from which the cascade suddenly bends off near Scheat, in an opposite course, 
and finally disappears in the mouth of the Southern Fish, 30° S. of Y. 

History. — This constellation is the famous Ganymede, a beautiful youth of 
Phrygia. son of Tros, king of Troy, or, according to Lucian, son of Dardanus. 
He was taken up to heaven by Jupiter as he was lending his father's flocks on 
Mount Ida. and became the cup-bearer of the gods in place of Hebe. There are 
various opinions, however, among the ancients respecting its origin. Some sup- 
pose it represents Deucalion, who was placed among the stars after the celebrated 
deluge of Thessaly, 1500 years before the birth of our Saviour; while others 
think it designed to commemorate Cecrops, who came from Egypt to Greece, 
founded Athens, established science, and introduced the arts of polished life. 

The ancient Egyptians supposed the setting or disappearance of Aquarius 
cau-ed the Nile to rise, by the sinking of his urn in the water. — In the Zodiac of 
the Hebrews, Aquarius represents the tribe of Reuben. 



PISCES AUSTRALIS, VEL NOTIUS. 

The Southern Fish. — This constellation is directly S. of 
Aquarius, and is represenied as a fish drinking the water 
which Aquarius pours from his urn. Its mean declination is 
31° S. and its mean right ascension and time of passing the 
meridian are the same as those of Aquarius, and it is seen on 
the meridian at the same time, viz. on the 15th of October. 
It contains 24 visible stars, of which one is of the 1st magni- 
tude, or between the 1st and 2d, two are of the 3d, and five of 
the 4th. The first and most beautiful of all is Fomalhaut, 
situated in the mouth. This is 14° directly S. of Scheat in 
Aquarius, and may be seen passing the meridian low down 
in the southern hemisphere, on the 22d and 23d of October. 

* Pronounced Fo-ma-lo. 

"What is the name of the principal star in this constellation? What is its position! 
What star in the W. shoulder ? Describe the situation of Ancha. What is the position 
of Scheat and Fomalhaut J To tohat constellations is Fomalhaut common 7 Of what 
nautical importance is it? When does it culminate ? With what other stars does it 
form a large triangle ? How may you trace the stars in the cascade ? Describe the 
situation and appearance of the Southern Fish. What are iU mean right ascension 
and declination ? When is it on the meridian ? What i3 the whole number of ita stars? 
What is the magnitude or' its principal ones ? What are the name and position of the 
most brilliant star in the constellation ) When and where does it pas* 'he meridian 7 



VARIABLE AND DOUBLE STARS, ETC. 137 

Its position in the heavens has been determined with the 
greatest possible accuracy, to enable navigators to find their 
longitude at sea. 

The mode of doing this cannot be explained here. The problem is one of some 
difficulty. It consists in finding the angular distance between some star whose 
position is well known, and the moon when she is passing near it; also, the 
altitude of each, at the same instant, with good sextants. These data furnish the 
elements of a spherical triangle, the solution of which, after various intricate 
corrections, is made to result in the longitude of the given place. — See note to 
Arietes. In 1714, the British Parliament offered a reward of 10.000 pounds ster- 
ling, to any man who should discover a method of determining the longitude 
within 1°, or 60 geographic miles of the truth; 15.000 pounds to the man who 
should find it within 40 miles, and 20.000 pounds, if found within 30 miles. These 
rewards in part have been since distributed among eminent mathematicians, in 
Europe, agreeably to the respective merits of their discoveries. 

History. — This constellation is supposed to have taken its name from the 
transformation of Venus into the shape of a fish, when she fled, terrified at the 
horrible advances of the monster Typhon, as we have related in the mythology 
of the Fishes. — (See Pisces.) 



CHAPTER XIII. 

VARIABLE AND DOUBLE STARS— CLUSTERS— NEBULA. 

1. Variable Stars. — The periodical variations of bril- 
liancy to which some of the fixed stars are subject, may be 
reckoned among the most remarkable of their phenomena. 
Several stars, formerly distinguished by their splendor, have 
entirely disappeared ; others are now conspicuous which do 
not seem to have been visible to the ancient observers ; and 
there are some which alternately appear and disappear, or, 
at least, of which the light undergoes great periodic changes. 
Some seem to become gradually more obscure, as Delta in 
the Great Bear ; others, like Beta in the Whale, to be in- 
creasing in brilliancy. Some stars have all at once blazed 
forth with great splendor, and, after a gradual diminution of 
their light, again become extinct. The most remarkable 
instance of this kind is that of the star which appeared in 
1572. in the time of Tycho Brahe. It suddenly shone forth, 
in the constellation Cassiopeia, with a splendor exceeding 
that of stars of the first magnitude, even of Jupiter and of 
Venus, at their least distances from the earth ; and could be 
seen, with the naked eye, on the meridian, in full day ! Its 
Drilliancy gradually diminished from the time of its first ap- 
pearance, and at the end of sixteen months, it entirely disap- 

Fpr what purpose has its position been very accurately determined? Describe the 
periodical variations of brilliancy to which some of the fixed stars are subject) Men- 
tion some of the most remarkable instances of such variations, and describe them par- 
ticularly. 

12* 



138 DOUBLE STARS. 

peared, and has never been seen since. (See a more parti- 
cular account of this 'phenomenon, page 40.) 

Another instance of the same kind was observed in 1604, 
when a star of the first magnitude suddenly appeared in the 
right foot of Ophiuchus. It presented, like the former, all the 
phenomena of a prodigious flame, being, at first, of a dazzling 
white, then of a reddish yellow, and, lastly, of a leaden paltT- 
ness ; in which its light expired. These instances prove that 
the stars are subject to great physical revolutions. — Page 41. 

A great number of stars have been observed whose light 
seems to undergo a regular periodic increase and diminution. 
They are properly called Variable Stars. One in the Whale 
has a period of 334 days, and is remarkable for the magni- 
tude of its variations. From being a star of the second mag- 
nitude, it becomes so dim as to be seen with difficulty through 
powerful telescopes. Some are remarkable for the shortness 
of the period of their variation. Algol has a period of between 
two and three days ; Delta Cephei. of oh days ; Beta Lyrce, 
of 6 2-5 days: and Mu Anlinoi, of 7 days. 

The regular succession of these variations precludes the 
supposition of an actual destruction of the stars; neither can 
the variations be supposed to arise from a change of distance; 
for as the stars invariably retain their apparent places, it would 
be necessary to suppose that they approach to, and recede 
from the earth in straight lines, which is very improbable. 
The most probable supposition is, that the stars revolve, like 
the sun and planets, about an axis. " Such a motion," says 
the elder Herschel, " may be as evidently proved, as the 
diurnal motion of the earth. Dark spots, or large portions 
of the surface, less luminous than the rest, turned alternately 
in certain directions, either toward or from us, will account 
for all the phenomena of periodical changes in the luster of 
the stars, so satisfactorily, that we certainly need not look for 
any other cause." 

2. Double Stars. — On examining the stars with tele- 
scopes of considerable power, many of them are found to be 
composed of two or more stars, placed contiguous to each 
other, or of which the distance subtends a very minute angle. 
This appearance is. probably, in many cases, owing solely 
to the optical effect of their position relative to the spectator ; 
for it is evident that two stars will appear contiguous if they 

What are such stars denominated? Describe the variations of one in the Whale. 
What stars are remarkable tor the shortness of the period of their variations ? Why 
may we not suppose that the stars which disappear are actually destroyed ? Why may 
not the variations ari;e from a chanze of distance? What is the most probable suppo- 
sition in regard to their cause? How does Dr. Herschel explain these phenomena? 
On examining the stars with a telescope of considerable power, what other peculiarity 
do we find ? To what is this appearance, in many cases, owing; ? 



DOUBLE STARS. 139 

are placed nearly in the same line of vision, although their 
real distance may be immeasurably great. 

There are, however, many instances in which the angle 
of position of the two stars varies in such a manner as to 
indicate a revolution about each other and about a common 
center. In this case they are said to form a Binary System 
performing to each other the office of sun and planet, and are 
connected together by laws of gravitation like those which 
prevail in the solar system. The recent observations of Sir 
John Herschel and Sir James South, have established the 
truth of this singular fact, beyond a doubt. Motions have 
been detected, so rapid as to become measurable within very 
short periods of time; and at certain epochs, the satellite or 
feebler star has been observed to disappear, either passing 
behind or before the primary, or approaching so near to if 
that its light has been absorbed by that of the other. 

The most remarkable instance of a regular revolution ol 
this sort, is that of Mizar, in the tail of the Great Bear ; in 
which the angular motion is 6 degrees and 24 minutes of a 
great circle, annually; so that the two stars complete arevo 
lution about one another in the space of 5Si years. Abou 
eleven twelfths of a complete circuit have been already de 
scribed since its discovery in 178 1, the same year in which 
the planet Herschel was discovered. 

A double star in Ophiuchus presents a similar phenomenon, 
and the satellite has a motion in its orbit still more rapid. 
Castor in the Twins,* Gamma Virginis, Zeta in the Crab, 
Zi Bootis, Delta Serpentis, and that remarkable double star 
61 Cygni, together with several others, amounting to 40 in 
number.f exhibit the same evidence of a revolution about each 
other and about a common center. But it is to be remem- 
bered that these are not the revolutions of bodies of a planet- 
ary nature around a solar center, but of sun around sun — 
each, perhaps, accompanied by its train of planets, and their 
satellites, closely shrouded from our view by the splendor 
of their respective suns, and crowded into a space bearing 
hardly a greater proportion to the enormous interval which 
separates them, than the distances of the satellites of our 

* Page 67. t Herschel's Astronomy, page 391. 

Are there, however, any instances where one star revolves with another around a 
common center? When two stars are thus situated, what system are they said to 
form.' Why is it thus denominated ? What modern astronomers of great celebrity 
have established the truth of this theory? What rates of motion did they detect m 
these binary systems ? What other interesting phenomena, indicating a mutual revo- 
lution, did they discover? What is the most remarkable instance of this fact ? Men- 
tion some other instances. Are these revolving stars of a planetary nature ? Of what 
nature are they ? 



140 DOUBLE STARS. 

planets from their primaries, bear to their distances from tlie 
sun itself. 

The examination of double stars was first undertaken by the late Sir William 
Herschel, with a view to the question of parallax. His attention was, however, 
soon arrested by the new and unexpected phenomena which these bodies pre- 
sented. Sir William observed of them, in all, 2400. Sir James South and Her- 
schel have given a catalogue of 380 in the Transactions of the Royal Society for 
1624, and South added 453 in 1826. Sir John Herschel, in addition to the above, 
published an account, of 1000, before he left England for the Cape of Good Hope. 
where he is, at the time we write, pushing his discoveries in the southern hem- 
isphere with great perseverance and success. Professor Siruve, with the great 
Dorpat telescope, has given a catalogue of 3.063 of the most remarkable of these 
stars. 

The object of these catalogues is not merely to fix the place of the star within 
such limits as will enable us easily to discover it at any future time, but also to 
record a description of the appearance, position, and mutual distances of the 
individual stars composing the system, in order that subsequent observers may 
have the means of detecting their connected motions, or any changes which they 
may exhibit. Professor Strove has also taken notice of 52 triple stars, among 
which No. 11 of the Unicorn, Zeta of Cancer, and Zi of the Balance, appear to 
be ternary systems in motion. Quadruple and quintuple stars have likewise 
been observed, which also appear to revolve about a common center of gravity ; 
in short, every region of the heavens furnishes examples of these curious phe 
nomena. 

Color of the Stars. — Many of the double stars exhibit the 
curious and beautiful phenomenon of contrasted colors, or 
complimentary tints. In such instances, the larger star is 
usually of a ruddy or orange hue, while the smaller one ap- 
pears blue or green, probably in virtue of that general law 
of optics, which provides, that when the retina is under the 
influence of excitement by any bright, colored light, feebler 
lights, which seen alone would produce no sensation but that 
of whiteness, shall for the time appear colored with the tint 
complimentary to that of the brighter. Thus, a yellow color 
predominating in the light of the brighter star, that of the less 
bright one, in the same field of view, will appear blue ; while, 
if the tint of the brighter star verge to crimson, that of the 
other will exhibit a tendency to green — or even appear a 
vivid green. The former contrast is beautifully exhibited 
by Iota, in Cancer; the latter by Almaack, in Andromeda — 
both fine double stars. If, however, the colored star be much 
the less bright of the two, it will not materially affect the 
other. Thus, for instance, Eta Cassiopeise exhibits the beau- 
tiful combination of a large white star, and a small one of a 
rich ruddy purple. 

It is not easy to conceive what variety of illumination two 
suns — a red and a green, or a yellow and a blue one — must 
afford to a planet revolving about either; and what charming 

What beautiful and curious phenomenon has been observed, as it regards the color of 
double stars ? Explain how these colors are usually contrasted. Mention an example 
of this phenomenon. How, if the colored star be much the less bright of the two, will 
the other be affected ? Give an instance. What may be the effect of such a variety ot 
riolor in solar light .' 



CLUSTERS. 141 

contrasts and grateful vicissitudes — a red and a green day, 
for instance, alternating with a white one and with darkness 
— might arise from the presence or absence of one or the 
other, or both, above the horizon. Insulated stars of a red 
color, almost as deep as that of blood, occur in many parts 
of the heavens, but no green or blue star (of any decided hue) 
has, we believe, ever been noticed, unassociated with a com- 
panion brighter than itself. 

3. Clusters. — When we cast our eyes over the concave sur- 
face of the heavens in a clear night, Ave do not fail to observe 
that there are, here and there, groups of stars which seem 
to be compressed togeuher more densely than those in the 
neighboring parts ; forming bright patches and clusters. 

There is a group called the Pleiades, in which six or seven 
stars may be noticed, if the eye be directed full upon it; and 
many more if the eye be turned carelessly aside, while the at- 
tention is kept directed* upon the group. Telescopes show 
fifty or sixty large stars thus crowded together in a very mod- 
erate space, and comparatively insulated from the rest of 
the heavens. Rheita affirms that he counted 200 stars in 
this small cluster. The constellation, called Coma Berenices. 
is another group, more diffused, and consisting of much lar- 
ger stars. 

In the constellation Cancer, there is a nebulous cluster of 
very minute stars, called Praisepe, or the Beehive, which is 
sufficiently luminous to be seen by the naked eye, in the ab- 
sence of the moon, and which any ordinary spyglass will re- 
solve into separate stars. In the sword-handle of Perseus, 
also, is another such spot, crowded with stars. It requires, 
however, rather a better telescope to resolve it into indivi- 
dual stars. 

These are called Clusters of Stars. Whatever be their 
nature, it is certain that other laws of aggregation subsist in 
these spots, than those which have determined the scattering 
of stars over the general surface of the sky. Many of them, 
indeed, are of an exactly round figure, and convey the idea 
of a globular space filled full of stars, and constituting, in 
itself, a family or society apart, and subject only to its own 
internal laws. 

" It would be a vain task," says the younger Herschel, " to 

;• "It is a very remarkable fact," says Sir John Herschel, "that the center of the 
visual ortian is by far less sensible to feeble impressions of light, than the exterior por- 
tions of the retina."— Ast. p. 398. 

Are individual stars of a deep color ever found separate from others? "What are 
clusters ot stars ? Mention some instance. Describe it. Mention some other instance. 
Describe the position and appearance of Prcesepe. Describe any other cluster which 
you may recollect. What are the constitution and figure of such croups? What did 
the younger Herschel say of the number of stars which compose these clusters? 



142 NEBULZB. 

attempt to count the stars in one of these globular clusters. 
They are not to be reckoned by hundreds; for it would ap- 
pear that many clusters of this description must contain, at 
feast, ten or twenty thousand stars, compacted and wedged 
together in a round space, not more than a tenth part as large 
as that which is covered by the moon. 

i. Nebulae. — The Nebulae, so called from their dim, cloudy 
appearance, form another class of objects which furnish mat- 
ter for curious speculation and conjecture respecting the for- 
mation and structure of the sidereal heavens. When exam- 
ined with a telescope of moderate powers, the greater part 
of the nebulae are distinctly perceived to be composed of 
little stars, imperceptible to the naked eye, because, on ac- 
count of their apparent proximity, the rays of light proceed- 
ing from each are blended together, in such a manner as to 
produce only a confused luminous appearance. 

In other nebulas, however, no individual stars can be per- 
ceived, even through the best telescopes; and the nebula? 
exhibit only the appearance of a self-luminous phosphores- 
cent patch of gaseous vapor, though it is possible that even 
in this case, the appearance may be owing to a congeries of 
stars so minute, or so distant, as not to afford, singly, sufficient 
light to make an impression on the eye. 

In some instances a nebula presents the appearance of a 
faint luminous atmosphere, of a circular form, and of large 
extent, surrounding a central star of considerable brilliancy. 

One of the most remarkable nebulae is in the sword-handle 
of Orion. It is formed of little flocky masses, like wisps of 
cloud, which seem to adhere to many small stars at its out- 
skirts. It is not very unlike the mottling of the sun's disc, 
but of a coarser grain, and with darker intervals. These wisps 
of light, however, present no appearance of being composed 
of small stars; but in the intervals between them, we fancy 
that we see stars, or that, could we strain our sight a little 
more, we should see them. These intervals may be com- 
pared to openings in the firmament, through which, as through 
a window, we seem to get a glimpse of other heavens, and 
brighter regions beyond. — Page 58. 

Another very remarkable nebula is that in the girdle of 
Andromeda, which, on account of its being visible to the 
naked eye, has been known since the earliest ages of astron- 
omy. It is often mistaken for a comet, by those unacquainted 

"Why are the nebulae so called? Describe the usual appearances of nebute, as seen- 
throug h a telescope. What other appearance do nebulae sometime* exhibit ? Mention 
some instance? of the most remarkable nebula. Describe the one in the •word-handle 
of Orion. Describe the one which is in the girdle of Andromeda. 



NEBULA. 143 

with the heavens. Marius. who noticed it in 1612, describes 
its appearance as that of a candle shining through horn ; and 
the resemblance is certainly very striking. Its form is a long 
oval, increasing, by insensible gradations of brightness, from 
the circumference to a central point, which, though very much 
brighter than the rest, is not a star, but only a nebula in a 
high state of condensation. No power of vision hitherto di- 
rected to this nebula has been able to resolve it into the least 
appearance of stars. It occupies an area comparatively large 
— equal to that of the moon in quadrature. This nebula may 
be considered as a type, on a large scale, of a very numerous 
class of nebulae, of a round or oval figure, increasing more or 
less in density toward the center. 

Annular nebula also exist, but are among the rarest ob- 
jects in the heavens. The most conspicuous of this class, is 
to be found exactly half-way between the stars Beta and 
Gamma Lyrce, and may be seen with a telescope of moderate 
power. It is small, and particularly well defined ; appearing 
like a flat oval ring. The central opening is not entirely 
dark, but is filled with a faint, hazy light, uniformly spread 
over it, like a fine gauze stretched over a hoop. 

Planetary nebula are very extraordinary objects. They 
have, as their name imports, the appearance of planets, with 
round or slightly oval discs, somewhat mottled, but approach- 
ing, in some instances, to the vividness of actual planets. 
Some of them, upon the supposition that they are equally 
distant from us with the stars, must be of enormous magni- 
tude. That one, for instance, which is situated in the left 
hand of Aquarius, must have a volume vast enough, upon 
the lowest computation, to fill the whole orbit of Herschel ! 

The nebulae furnish an inexhaustible field of speculation 
and conjecture. That by far the larger number of them con- 
sists of stars, there can be little doubt; and in the intermina- 
ble range of system upon system, and firmament upon firma- 
ment, which we thus catch a glimpse of, the imagination is 
bewildered and lost. Sir William Herschel conjectured that 
the nebulae might form the materials out of which nature 
elaborated new suns and systems, or replenished the wa.sted 
light of older ones. But the little we know of the physical 
constitution of these sidereal masses, is altogether insufficient 
to warrant such a conclusion. 

Of what class of nebulas may this be considered as a type ? What other species of 
nebuhr exist in the heavens? Describe the uio*t conspicuous of this class. What 
other species of nebula.' art; more rarely found .' DeM-.ribe the appearance of planetary 
aebuie. What do we know in ■< :;arn V> their maLMiitu.ie ? H<>u l.irue must ihe one be 
which is situated in the left hand of Aquariin .' Vt'hat ,:i,| Sjr \Vi ham Herschel con 
Have we 1'acf.i sutri.-itni to warrant suen a cxjii 



144 VIA LACTEA, OR [MAP VIIL 

CHAPTER XIV. 
VIA LACTEA. 

" Throughout the Galaxy's extended line, 
Unnumberd orbs in gay confusion shine : 
Where every star that gilds the gloom «f night 
With the faint tremblings of a distant light, 
Perhaps illumes some system of its own. 
With the strong influence of a radiant sun." — Mrs. Carter. 

There is a luminous zone or pathway of singular white- 
ness, varying from 4° to 20° in width, which passes quite 
round the heavens. The Greeks called it Galaxy, on ac- 
count of its color and appearance: the Latins, for the same 
reason, called it Via Lactea, which, in our tongue, is Milky 
Way. 

Of all the constellations which the heavens exhibit to our 
view, this fills the mind with the most indescribable grandeur 
and amazement. When we consider what unnumbered 
millions of mighty suns compose this cluster, whose distance 
is so vast that the strongest telescope can hardly separate 
their mingled twilight into distinct specks, and that the most 
contiguous of any two of them may be as far asunder as our 
sun is from them, we fall as far short of adequate language 
to express our ideas of such immensity, as we do of instru- 
ments to measure its boundaries. 

It is one of the recent achievements of astronomy that has 
resolved the Milky-Way into an infinite number of small 
stars, whose confused and feeble luster occasions that pecu- 
liar whiteness which we see in a clear evening, when the 
moon is absent. It is also a recent and well-accredited doc- 
trine of astronomy, that all the stars in the universe are ar- 
ranged into clusters, or groups, which are called Nebulae or 
Starry Systems, each of which consists of many thousands 
of stars 

The fixed star which we call our Sun, belongs, it is said, 
to that extensive nebula, the Milky- Way; and although ap- 
parently at such an immeasurable distance from its fellows, 
is, doubtless, as near to any one of them, as they are to one 
another. 

Of the number and economy of the stars which compose 
this group, we have very little exact knowledge. Dr. Her- 
schel informs us that, with his best glasses, lie saw and 

What do you understand by the Milky Way? Bv what different namea u it called » 
Why does the contemplation of this constellation fill the mind with ideas of grandeui 
and amazement? What causes the whiteness of the Milky- Way? Into what are all 
the stars in the universe arranged? To wh it nebula? does tho sun belong, and what it 
probably its distance from its fellows ) What knowledge have we o. the number and 
economy of the stars in this group ? 



MAP VIII.] MILKY-WAY. 145 

counted 588 stars m a single spot, without moving his tele- 
scope ; and as the gradual motion of the earth carried these 
out of view and introduced others successively in their places^ 
while he kept his telescope steadily fixed to one point, M there 
passed over his field of vision, in the space of one quarter of 
an hour, no less than one hundred and sixteen thousand star» s 
and at another time, in forty-one minutes, no less than twa 
hundred and fifty -eight thousand." 

In all parts of the Milky- Way he found the stars unequally 
dispersed, and appearing to arrange themselves into separate 
clusters. In the small space, for example, between Beta and 
Sad'r. in Cygni. the stars seem to be clustering in two divi- 
sions; each division containing upwards of one hundred and 
sixty-five thousand stars. 

At other observations, when examining a section of the 
Milky- Way, not apparently more than a yard in breadth, and 
six in length, he disco vered fifty thousand stars, large enough 
to be distinctly counted ; and he suspected twice as many 
more, which, for want of sufficient light in his telescope, he 
saw only now and then. 

It appears from numerous observations,that various changes 
are taking place among the nebulae — that several nebulae are 
formed by the dissolution of larger ones, and that many ne- 
bula of this kind are at present detaching themselves from 
the Milky-Way. In hat part of it which is in the body of 
Scorpio, there is a large opening, about 4° broad, almost 
destitute of stars. These changes seem to indicate thai 
mighty movements and vast operations are continually going 
on in the distant regions of the universe, upon a scale of mag- 
nitude and grandeur which baffles the human understanding. 

More than two thousand five hundred nebulae have already 
been observed; and, if each of them contains as many slara 
as the Milky- Way, several hundreds of millions of stars must 
exist, even within that portion of the heavens which lies open 
to our observation. 

" O what a confluence of ethereal fires. 
From urns uuntimber'd down the steep of heaven 
Streams to a point, and centers on my sight." 

Although the Milky- Way is more or less visible at all 
seasons of the year. yet. it is seen to the best advantage du- 
ring the months of July, August, September, and October. 
When Lyra is on, or near the meridian, it may be see-n 

How many did Dr. Herschel count in a single spot d urine the space of 15 minutes J 
How di I he find the stor< dispersed, throughout the Mi Iky- Way? Give an example. 
Give another instance. Whiit chum-es ;ire taking place in the Milky-Way (Ttid other 
hebulx ! Wh.U do thc-e chain-en indicate .' How many nrhnl.e hue bee a discovered J 
If each of the-e nebula- contains an many stars as the Mi Iky- Way, how many star* 
must exist even in tint portion uf the In wus which lie* open to our observation? 
Where and at what period may the Milky-Way be seen to the best advantage J 

13 



146 ORIGIN OF THE 

stretching obliquely over the heavens from north-east to south- 
west, gradually moving over the firmament in common with 
other constellations. 

Its form, breadth and appearance are various, in different 
parts of its course. In some places it is dense and luminous ; 
in others, it is scattered and faint. Its breadth is often not 
more than five degrees ; though sometimes it is ten or fifteen 
degrees, and even twenty. In some places it assumes a 
double path, but for ihe most part it is single. 

It may be tracer! In the heavens, beginning near the head of Cepheus, about 
•50° from the north pole, through the constellations Cassiopeia. Perseus, Auriga, 
and part of Orion and the feet of Gemini, where it crosses the Zodiac ; thence 
over the equinoctial into the southern hemisphere, through Monoceros, and the 
middle of the ship Argo, where it is most luminous, Charles' Oak. the Cross, the 
feet of the Centaur, and the Altar. Here it is divided into two branches, as it 
pa»os over the Zodiac again into the northern hemisphere. One branch runs 
through the tail of Scorpio, the bow of Sagittarius, the shield of Sobieski, the feet 
Of Antinous, Aqnila, Delphinus, the Arrow, and the Swan. Tiie other branch 
passes through the upper part of the tail of Scorpio, the side of Serpentarius, 
Taurus Poniatowski. the Goose and the neck of the Swan, where it again unites 
with the other branch, and passes on to the head of Cepheus, the place of its be- 
■ ginning. 

There are several other nebulce in the heavens as large as 
the Milky-Way, but not visible to the naked eye, which may 
exhibit the phenomenon of a lucid zone to the planetary 
worlds that may be placed within them. 

Some of the pagan philosophers maintained that the Milky-Way was formerly 
the sun's path, and that its present luminous appearance is the track which ius 
'scattered beams left visible in Ihe heavens. 

The ancient poets and even philosophers, speak of the Galaxy, or Milky-Way, 
hs the path which their deities u<ed in the heavens, an 1 which fed directly to the 
throne of Jupiter. "Thus, Ovid, in his Metamorphoses, Book i. : — 

" A way there is in heaven's extended plain, 

Which when the skies are clear is ^een below, 

And mortals, by the name of Milky, know ; 

The groundwork is of stars, ihroimh which the road 

Lies open to the Thunderer's abode." 
Milton alludes to this, in the following lines : — 

" A broad and ample road, whose dust is gold, 

And pavement, stars, as stars to thee appear, 

Seen 'in the Galaxy, that Milky Way, 

Which nightly as a circling zone, thou seest 

Powdered with stars." 



CHAPTER XV. 

ORIGIN OF THE CONSTELLATIONS. 

The science of astronomy was cultivated by the immediate 
descendants of Adam. Josephus informs us that the sons 

Describe the breadth and appearance of the Milky-Way. Hoio may it be traced in 
the heavens? Are the e other nebula; in Hie heavens as large a< the Milky-Way / How 
early was the science of astronomy cultivated; What authority have we tor aiTiunjt 
m early a date to the science i 



CONSTELLATION'S. 147 

of Seth employed themselves in the study of astronomy; 
and that they wrote their observations upon two pillars, one 
of brick, and the other of stone.* in order to preserve them 
against the destruction which Adam had foretold should come 
upon the earth. He also relates, that Abraham argued the 
unity and power of God. from the orderly course of things? 
both at sea and land, in their times and seasons, and from hie 
observations upon the motions and influences of the sun. 
moon, and stars ; and that he read lectures in astronomy and 
arithmetic to the Egyptians, of which they understood noth- 
ing till Abraham brought these sciences from Chaldea to 
Egypt; from whence they passed lo the Greeks. 

Berosus also observes that Abraham was a great and just 
man. and famous for his celestial observations; the making 
}f which was thought to be so necessary to the human wel- 
fare, that he assigns it as the principal reason of the Al- 
mighty's prolonging the life of man. This ancient historian 
tells us, in his account of the longevity of the antediluvians, 
that Providence found it necessary to prolong man's days, in 
order to promote the study and advancement of virtue, and 
the improvement of geometry and astronomy, which required, 
at least, six hundred years for making and perfecting obser- 
vations.! 

When Alexander took Babylon. Calisthenes found that the 
most ancient observations existing on record in that city, were 
made by the Chaldeans about 1903 years before that period, 
which carries us back to the time of the dispersion of mankind 
by the confusion of tongues. It was 1500 years after this 
that the Babylonians sent to Hezekiah, to inquire about the 
shadow's going back on the dial of Ahaz. 

It is therefore very probable that the Chaldeans and Egyp- 
tians were the original inventors of astronomy; but at what 
period of the world they marked out the heavens into con- 
stellations, remains in uncertainty. La Place fixes the date 
thirteen or fourteen hundred years before the Christian era^ 
since it was about this period, that Eudoxus constructed the 
first, celestial sphere upon which the constellations were de- 

• Josephus affirms, that " he saw himself that of stone to remain in Syria in his own 
time. ' 
t Vince's Complete System of Astronomy, Vol. ii. p. 211. 

What does Josephus relate concerning Abraham's knowledge of astronomy ! Who, 
foes hi say, first introduced tins science into Ksjpt ? What other historian of remote 
antiquity speaks of Abraham's attention to this science ? What reason does Berosus 
as-ii-ii for the longevity of the antediluvians 3 When Alexander took Bah> Ion, what 
observations did he find inthatci'y? Towh.it period of the world <!o these 
observations carry us back .' How long after this was it that the Babylonians sentM 
Hezekiah, to inquire about the shadow "s -ointr ba^k on the dial of Ahaz » Who. then. 
■lay we conclude, we^e the original inventors of astronomy, and at what period did 
they arrange the fixed stars into constellations ! When does La Place fix the date ? 



148 ORIGIN OF THE 

lineated.* Sir Isaac Newton was of opinion, that all the old 
constellations related to the Argonautic expedition, and that 
ihey were invented to commemorate the heroes and events 
of that memorable enterprise. It should be remarked, how- 
ever, that while none of the ancient constellations refer to 
transactions of a later date, yet we have various accounts of 
»hem, of a much higher antiquity than that event 

Some of the most learned antiquarians of Europe have 
searched every page of heathen mythology, and ransacked al. 
the legends of poetry and fable ibr the purpose of rescuing 
this subject from that impermeable mist which rests upon it, 
and they have only been able to assure us. in general terms, 
that they are Chaldean or Egyptian hieroglyphics, intended 
to perpetuate. by means of an imperishable record, the memory 
of the times in which their inventors lived, their religion and 
manners, their achievements in the arts, and whatever in 
their history was most worthy of being commemorated. There 
was, at least, a moral grandeur in this idea ; ibr an event thus 
registered, a custom thus canonized, or thus enrolled among 
the stars, must needs survive all other traditions of men. and 
stand forth in perpetual characters to the end of time. 

In arranging the constellations of the Zodiac, for instance, 
it would be natural for them, we may imagine, to represent 
those stars which rose with the sun in the spring of the year, 
by such animals as the shepherds held in the greatest esteem 
at that season; accordingly, we find Aries, Taurus, and 
Gemini, as the symbols of March, April, and May. 



* The usual .size of artificial globes. designed to represent the celestial sphere, is 
from 9 to IS niches in diameter. Globes have been recently constructed m Geimany, 
which are saia to be more splendid and complete than any in the world. The largest 
ever wade are thrtt of Gotforp, two in tiie library of the late king of France, and one in 
Pembroke college, Camhridge. 

The globe of Gottorp. now in the Academy of Sciences at Petersburg, is a laige hol- 
low sphere, eleven and a half feet in diameter, containing a table ami seats lor l« the 
persons. The inside represents the visible surface of the heavens, bespangled with 
gilded star-;, ranged in their proper order and magnitude, and by means of a curious 
piece of mechanism by which it is put in motion, exhibits the true position of ihe stars, 
b*. any time, together with their rising and setting. The convex surface, or outside of 
ihis globe, represents the terrestrial sphere. 

In 1704. twodobes of equal dimensions, it is said, were made fir Cardinal d'Estrees, 
by Cornelh. a Venitian, and deposited m the king's library at 1'aris. The~e. however, 
are fir inferior in size to one of similar construction, ejected at Pembiokt college, in 
the University of Cambridge, by the lite Dr. Lonu, president of that institution. This 
is a hollow sphere, sufficiently capacious to admit thirty persons to sit within it. where 
they can observe the artificial world of stars and planets, revolving over their heads, in 
the same order as they are seen m the heavens. This sphere is eighteen feet in dia- 
meter. 



What opinion has Sir Isaac Newton advanced upon this subject? Have we. however, 
any accounts of the constellations, of a hi-'her antiquity than that event? Ho any of 
the ancient constellations refer to transactions of a later date ' What have the most 
learned antiquarians of Europe done upon this subject, and of what no they - 
How long would the memory of an action, or event, thus registered, be likely to en 
dure? In arranging the constellations of the Zodiac, how was it natural to represent 
the stars ? 



CONSTELLATIONS. 1 49 

When the sun enters the sign Cancer, at the summer sol- 
stice, he discontinues his progress toward the north pole, and 
begins to return toward the south po.e. This r°trograde 
motion was fitly represented by a Crab, which is said lo go- 
backward. The sun enters this sign about the 22d of June. 

The heat which usually follows in the next month was 
represented by the Lion ; an animal remarkable for its fierce- 
ness, and which at this season was frequently impelled by 
thirst to leave the sandy desert, and make its appearance on 
the banks of the Nile. 

The sun entered the sixth sign about the time of harvest, 
which season was therefore represented by a Virgin, or female 
reaper, with an ear of corn in her hand. 

At the autumnal equinox, when the sun enters Libra, the 
days and nights are equal all over the world, and seem to 
observe an equilibrium or balance. The sign was therefore 
represented under the symbol of a pair of Scales. 

Autumn, which produces fruit in great abundance, brings 
with it a variety of diseases, and on this account was repre- 
sented by that venomous animal, the Scorpion, which, as he 
recedes, wounds with astingin his tail. The fall of the leaf, 
was the season for hunting, and the stars which mark the 
sun's path at this time were represented by a huntsman, or 
archer, with his arrows and weapons of destruction. 

The Goat, which delights in climbing and ascending some 
mountain or precipice, is the emblem of the winter solstice^ 
when the sun begins to ascend from the southern tropic, and 
gradually to increase in height for the ensuing half year. 

Aquarius, or the Water-Bearer, is represented by the figure 
of a man pouring out water from an urn, an emblem of the 
dreary and uncomfortable season of winter. 

The last of the zodiacal constellations was Pisces, or a 
couple of fishes, tied back to back, representing the fishing 
season. The severity of winter is over ; the flocks do not 
afford sustenance, but the seas and rivers are open and 
abound with fish. 

»■ Thus monstrous forms, o'er heaven's nocturnal arch, 
Seen by the sage, in pomp celestial march ; 
See Aries there his glittering bow untold, 
And raging Taurus toss his horns of gold ; 
With bended bow the sullen Archer lowers, 
And there Aquarius comes with all his showers; 

What sign was represented under the figure of a Crab, and why? "When docs the 
6tin enter this sign .' What, nnimol represented the heat of summer, and why ? When 
does the sun eater the sixth sign, ami how is tins season represented > Why was the 
sign which thtrsun enters at the autumnal equinox represented under the symbol of a 
Balance? Why were the autumnal signs. Scorpio and Sagittarius, represented as they 
are' What does the Coat represent ? What is signified by the Water- Bearer 1 What 
do the Fishes represent? 

13* 



150 ORIGIN OF THE 

Lions and Centaurs, Gordons. Hydras rise, 
And gods and heroes blaze along the skies."* 

Whatever may have led to the adoption of these rude names 
at first, they are now retained to avoid confusion. 

The early Greeks, however, displaced many of the Chal- 
dean constellations, and substituted such images in their place 
as had a more special reference to their own history. The 
Romans, aiso pursued the same course with regard to their 
history ; and hence the contradictory accounts that have 
descended to later times. 

Some, moreover, with a desire to divest the science of the 
stars of its pagan jargon and profanity, have been induced 
to alter both the names and figures of the constellations. In 
doing this, they have committed the opposite fault; that of 
blending them with things sacred. The "venerable Bede," 
for example, instead of the profane names and figures of the 
twelve constellations of the Zodiac, substituted those of the 
twelve apostles. Julius Schillerius. following his example, 
completed the reformation in 1627, by giving Scripture names 
to all the constellations in the heavens. Weigelius. too. a 
celebrated professor of mathematics in the university of Jena, 
made a new order of constellations, by converting the firma- 
ment into a ccelum heraldicum, in which he introduced the 
arms of all the princes of Europe. But astronomers, gene- 
rally, never approved of these innovations ; and for ourselves, 
we had as lief the sages and heroes of antiquity should con- 
tinue to enjoy their fiancied honors in the sky, as to see their 
places supplied by the princes of Europe. 

The number of the old constellations, including those of 
the Zodiac, was only forty-eight. As men advanced in the 
knowledge of the stars, they discovered many, but chiefly in 
southern latitudes, which were not embraced in the old con- 
stellations, and hence arose that, mixture of ancient and mod- 
ern names which we meet with in modern catalogues. 

* The order of the sisns is thus described by Dr. Watts :- 

The Ram, the BuU, the heavenly Twins ; 

And, next the Crab, the Lion shines, 

The Virgin, and the Scales ; 

The Scorpion, Archer, and Sea- Goat, 

The Man that holds 'he Water-Pot, 

And Fish, with glittering tails. 
Similar to this are the Latin verses .— 

• Sunt, aries, taurus, geminl, cancer, leo. v-b?o, 

Librasjue, scorpews, arcitenem, caper, amphora, pisce-s. 

Why have attempts been made to change the names and figures of^he ancient con- 
stellations ' What fault has been committed in doing this? What did the venerable 
Bede substitute for the profane names and figures of the twelve constellations of the 
Zodiac' Who followed his example, and to what extent? What other change was 

attempted, and by whom ' Have astronome-s generally approved of these innovations ? 
What was the number of the old constellations.' Whence is the mixture of ancient 
Mid modern names which we meet with in modern catalogues? 



CONSTELLATIONS. 151 

Astronomers divide the heavens into three parts, called the 
Northern and Southern Hemispheres, and the Zodiac. In the 
northern hemisphere, astronomers usually reckon thirty-four 
constellations, in the Zodiac twelve, and in the southern 
hemisphere forty-seven ; making in all, ninety-three. Besides 
these, there are a iew of inferior note, recently formed, which 
are not considered sufficiently important to be particularly 
described. 

About, the year 1603, John Bayer, a native of Germany, 
invented the convenient system of denoting the stars in each 
constellation by the letters of the Greek alphabet, applying 
to the largest star the first letter of the alphabet; to the next 
largest the second letter, and so on to the last. Where there 
are more stars in the constellation than there are Greek let- 
ters, the remainder are denoted by the letters of the Roman 
alphabet, and sometimes by figures. By this system of no- 
tation, it is now as easy to refer to any particular star in the 
heavens, as to any particular house in a populous city, by its 
street and number. 

Before this practice was adopted, it was customary to de- 
note the stars by referring them to their respective situations 
in. the figure of the constellation to which they severally be- 
longed, as the head, the arm, the foot, &c. 

It is hardly necessary to remark that these figures, which 
are all very curiously depicted upon artificial globes and maps 
are, purely, a fanciful invention — answering many convenient 
ends, however, for purposes of reference and classification, as 
they enable us to designate with facility any particular star, 
or cluster of stars ; though these clusters very rarely, if ever, 
represent the real figures of the object whose names they bear. 
And yet it is somewhat remarkable that the name of -'Great 
Bear," for instance, should have been given to the very same 
constellation by a nation of American aborigines, (the Iro- 
quois,) and by the most ancient Arabs of Asia, when there 
never had been any communication between them ! Among 
other nations, also, between whom there exists no evidence 
of any intercourse, we find the Zodiac divided into the same 
number of constellations, and these distinguished by nearly 
the same names, representing the twelve months, or seasons 
of the year. 

The history of this whimsical personification of the stars 
carries us back to the earliest times, and introduces us, as we 
have seen, to the languages and customs, the religion and 



How do astronomers usually divide the heavens, and what is the number of constel- 
lations in each division? What convenient system of notation has been invented for 
denoting the stars in each constellation » Who invented this system ? Before this me- 
thod was introduced, what was the practice .' 



152 NUMBER, DISTANCE, AND 

poetry, the sciences and arts, the tastes, talents, and peculiar 
genius, of the early nations of the earth. The ancient Atlan- 
tides and Ethiopians, the Egyptian priests, the magi of Per- 
sia, the shepherds of Chaldea, the Bramins of India, the man- 
darins of China, the Phenician navigators, the philosophers 
of Greece, and ihe wandering Arabs, have all added more 
or less to these curious absurdities and ingenious inventions, 
and have thus registered among the stars, as in a sort of 
album, some memorial of themselves and of the times in 
which they lived. The constellations, or the uncouth figures 
by which ihey are represented, are a faithful picture of the 
ruder stages of civilization. They ascend to times of which 
no other record exists ; and are destined to remain when all 
others shall be lost. Fragments of history, curious dates and 
documents relating to chronology, geography, and languages, 
are here preserved in imperishable characters. The adven- 
tures of the gods, and the inventions of men, the exploits of 
heroes, and the fancies of poets, are here spread out in the 
heavens, and perpetually celebrated before all nations. The 
Seven stars, and Orion, present themselves to us, as they 
appeared to Amos and Homer : as they appeared to Job, more 
than 3000 years ago, when the Almighty demanded of him — 
'•Knowest thou the ordinances of heaven ? Canst thou bind 
the sweet influences of the Pleiades, or loose the bands of 
Orion? Canst thou bring forth Mazzaroth in his season, 
or canst thou guide Arcturus with his sons?" Here, too, 
are consecrated the lyre of Orpheus and the ship of the Ar- 
gonauts ; and, in the same firmament, glitter the mariner's 
compass and the telescope of Herschel. 



CHAPTER XYT. 

NUMBER, DISTANCE, AND ECONOMY OF THE 
STARS. 

The first conjecture in relation to the distance of the fixed 
stars, is, that they are all placed at an equal distance from 
the observer, upon the visible surface of an immense concave 
vault, which rests upon the circular boundary of the world, 
and which we call the Firmament. 

We can, with the unassisted eye, form no estimate of their 
respective distances ; nor has the telescope yet enabled us to 
arrive at any exact results on this subject, although it has re- 
vealed to us many millions of stars that are as far removed 

# What, is the first conjecture which we form in relation to the distances of the fixed 
•tars ! What means have we tor ascertainin;; their number and distance .' 



ECONOMY OF THE STARS. 153 

beyond those which are barely visible to the naked eye. as 
these are from us. Viewed through the telescope, the hea- 
vens become quite another spectacle — not only to the un- 
derstanding, but to the senses. New worlds burst upon the 
sight, and old ones expand to a thousand times their former 
dimensions. Several of those little stars which but feebly 
twinkle on the unassisted eye. become immense globes. w T ith 
land and water, mountains and valleys, encompassed by at- 
mospheres, enlightened by moons, and diversified by day and 
night, summer and winter. 

Beyond these are other suns, giving light and life to other 
systems, not a thousand, or two thousand merely, but multi- 
plied without end, and ranged all around us, at immense dis- 
tances from each other, attended by ten thousand times ten 
thousand worlds, all in rapid motion; yet calm, regular and 
harmonious — all space seems to be illuminated, and every 
particle of light a world. 

It has been computed that one hundred millions of stars 
which cannot be discerned by the naked eye. are now visible 
through the telescope. And yet all this vast assemblage of 
suns and w T orlds may bear no greater proportion to what lies 
beyond the utmost boundaries of human vision, than a drop 
of water to <he ocean ; and, if stricken out of being, would 
be no more missed, to an eye that could take in the universe, 
than the fall of a single leaf from the forest. 

We should therefore learn (says an eminent divine of the 
present century,*) not to look on our earth as the universe of 
God, but as a single, insignificant atom of it; that it is only 
one of the many mansions which the Supreme Being has 
created for the accommodation of his worshipers ; and that 
he may now be at work in regions more distant than geome- 
try ever measured, creating worlds more manifold than num- 
bers ever reckoned, displaying his goodness, and spreading 
overall the intimate visitations of his care. 

Ti.e immense distance at which the nearest stars are known 
to be placed, proves that they are bodies of a prodigious size, 
not inferior to our sun, and that they shine, not by reflected 
rays, but by their own native light. It is therefore concluded, 
with good reason, that every fixed star is a sun, no less spa- 
cious than ours, surrounded by a retinue of planetary worlds, 



How do the heavens appear through the telescope 1 "What are beyond those little 
Stars which are scarcely visible to the naked eye ) How many stars are visible through 
the telescope ? What proportion may this vast a^sembla^e of suns and worlds I ear to 
what lies beyond the utmost boundaries or" human vision 7 How should we learn irom 
this to regard our own earth ' What does the immense distance of the stars prove in 
retard to their magnitude and light ? 



154 NUMBER, DISTANCE. AND 

which revolve around it as a center, and derive from it light 
and heat, and the agreeable vicissitudes of day and night. 

These vast globes of light, then, could never have been 
designed merely to diversify the voids of infinite space, nor 
to shed a few glimmering rays on our far distant world, for 
the amusement of a few astronomers, who, but for the most 
powerful telescopes, had never seen the ten thousandth part 
of them. We may therefore rationally conclude, that wher- 
ever the All-wise Creator has exerted his creative power, there 
also he has placed intelligent beings to adore his goodness. 

Hipparchus, the father of astronomy, first made a catalogue of the fixed stars. 
It contained 1022. The accuracy with which the places of these were recorded, 
has conferred essential benefit upon the science, and has enabled us so solve 
many celestial phenomena and problems of chronology, which otherwise had 
been difficult. 

Dnring the 18th century, upward of 100.000 were catalogued by the various 
astronomers of Europe, and their position in the heavens determined with an 
exactness that seldom varied a second from the truth ; insomuch that it has 
been justly remarked, that '-there is scarcely a star to be seen in the heavens, 
whose place and situation is not better known than that of most cities and towns 
upon the earth." 

But the star-gazers of our times are not idle. Professor Bessel of Konigs- 
berg, observed in three years, it is asserted, between 30.000 and 40.000 stars, 
Comprehended within a zone of 15° on each side of the equator ; but even this 
great number is but a small portion of the whole number which lie within the 
limit of the zone which lie examined. To procure a more complete survey, the 
academy of Berlin proposed that this same zone, should be parceled out among 
twenty-four observers, and that each should confine himself to an hour of riu;ht 
ascension, and examine it in minute detail. This plan was adopted ; and the 18th 
hour was confided to Professor Inshirami, of Florence, and examined with so 
much care, that the positions of 75.000 stars in it. have been determined. Pro- 
fessor M. Srruve. of the Dorpat university, has examined in person 120,000 stars, 
Of which SU0 (double ones) were before unknown to science. 

The labors of Sir Wm. Herschel were chiefly devoted to exploring the sys- 
tems of nebula? and double stars that lie, for the most part, beyond the reach "of 
ordinary telescopes. No fewer than two thousand five hundred nebulae were 
dBserved by this indefatigable astronomer, whose places have been computed 
from his observations, reduced to a common epoch, and arranged into a cata- 
logue in order of their right, ascension, by his sister Miss Caroline He::sciiel, 
a lady so justly celebrated in Europe for her astronomical knowledge and dis- 
coveries, but whose name, strange as it is. is seldom mentioned in this country. 
Be it remembered, nevertheless, for her fame, that she discovered two of the 
satellites of the planet which bears her brother's name, besides a multitude of 
comets. 

The greatest possible ingenuity and pains have been taken 
by astronomers to determine, at least, the approximate dis- 
tance of the nearest fixed stars. If they have hitherto been 
unable to arrive at any satisfactory result, they have, at least, 
established a limit beyond which the stars must necessarily 
be placed. If they have failed to calculate their true distan- 
ces from the earth, it is because they have not the requisite 
data. The solution of the problem, if they had the data, 
would not be more difficult than to compute the relative dis- 

"What conclusion may be drawn from this fact as to their preat design ? What pains 
have astronomers taken to find the distance of the -stars, and what result ha»e they 
come to ! For what reason have they failed to calculate their distance/ Is the prob- 
lem a difficult one? 



ECONOMY OF THE STARS. 155 

tances of the planets — a tiling which any school-boy can do. 
In estimating so great a distance as the nearest fixed star, 
it is necessary that we employ the longest measure which 
astronomy can use. Accordingly, we take the whole diame- 
ter of the earth's orbit, which, in round numbers, is 190 mil- 
lions of miles, and endeavor, by a simple process in mathema- 
tics, to ascertain how many measures of this length are con- 
tained in the mighty interval which separates us from the stars. 

The method of doing this can be explained to the appre- 
hension of the pupil, if he does not shrink from the illustra- 
tion, through an idle fear that it is beyond his capacity. 

For example ; suppose that, with an instrument construct- 
' ed for the purpose, we should this night take the precise bear- 
ing or angular direction from us of some star in the northern 
hemisphere, and note it down with the most perfect exact- 
ness, and, having waited just six months, when the earth 
shall have arrived at the opposite point of its orbit. 190 mil- 
lions of miles east of the place which we now occupy, we 
should then repeat our observation upon the same star, and 
see how much it had changed its position by our traveling 
so great a distance one side of it. Now, it is evident, that if 
it changes its apparent position at all. the quantity of the 
change will bear some proportion to the distance gone over; 
that is, the nearer the star, the greater the angle ; and the 
more remote the star, the less the angle. It is to be observ- 
ed, that the angle thus found, is called the star's Annual 
Parallax. 

But it is found by the most eminent astronomers of the 
age. and the most perfect instruments ever made, that this 
parallax does not exceed the four thousandth part of a de- 
gree, or a single second; so that, if the whole great orbit of 
the earth were lighted up into a globe of fire 6-0 millions of 
miles in circumference, it would be seen by the nearest star 
only as a twinkling atom ; and to an observer placed at this 
distance, our sun, with its whole retinue of planetary worlds, 
would occupy a space scarcely exceeding the thickness of a 
spider's we!;.* If the nearest of the fixed stars are placed at 



-• iJea of the import of this te-rn, will imnyrt a force and sublimity to an ex- 
pression of St. James, which no power of words conil improve. It ;- 
verse 17. oi Him from whom cometh down every good and perfect gilt, thai there is 
" ovk cvi rrapaWayrj 17 rpo-r,g a-rocxiacrfia. 1 ' Literally, There is "neither par- 
-hcaow of c> anise y As if the apostle ha. I said— Peradventure, th 
lions and millions of miles through the regions of immensity, th-'e may be 

of the fixed stars; yet, as to the Father of 1 
tever i oin: of his empire we may, lie is xoithout para:. 

matins the <!:st.incesof the fixed stars ? " 
: • What is the greatest magnitu 
umua! Da 



156 NUMBER, DISTANCE, AND 

such inconceivable distances in the regions of space, with 
what line shall we measure the distance of those which are 
a thousand or a million of times as much farther from them, 
as these are from us? 

If the annual parallax of a star were accurately known, it 
would be easy to compute its distance by the following rule: 
As the sine of the star's parallax : 
Is to radius, or ninety degrees: : 
So is the earth's distance from the sun: 
To the star's distance from the sun. 
If we allow the annual parallax of the nearest star to be 
i', the calculation will be, 
As 0.0000048481368=Nat. Sine of I". 
Is to 1.0000000000000=Nat. Sine of 90°. 
So is 95.273.S6S.S67748554= Earth's distance from the sun. 
To 19,65 1,627,683,449= Star's distance from the sun. 

In this calculation we have supposed the earth to be placed at the mean dis- 
tance of 24,017 of its own eemi-diameters, or 95.273,868.867748554 miles from the 
sun. which makes the star's distance averylitile less than twenty billions of 
miies. Dr. Herschel says that Sirius cannot be nearer than 100.000 times the 
diameter of the earth's orbit, or 19.007.78S,800.000 of miles. 

Bior. who either takes the earth's distance greater than he lays i( down in his 
Troite' Elementairc cV Astronomic Physique, or has made an error in figures, 
makes the distance 20,036,808 ,036.404. Dr. Brewster makes it 20.159,665.00 ( .,000 
miies. A mean of these computations, is 20 billions ; that is, 20 millions of 
millions of miles, to a parallax of 1". 

Astronomers are generally agreed in the opinion that the annual parallax of 
the stars is less than 1", and consequently that the nearest of them Is placed at 
a much greater distance from us, than these calculations make it. It was. how- 
ever, announced during the last year, that M. d'Assas. a French astronomer, 
had satisfactorily established the annual parallax of Keid. (a small star 8' N. of 
Gamma Eridani,) to be 2", that of RigeL in Orion, to be 1". 43, and lhat of Sirius 
to be 1". 24. If these results may he"relied on, Keid is but 10 billions. Rigel but 
14 billions, and S rius 16 billions of miles from the earth. This latter distance is, 
however, so great that, if Sirius were to fall toward the earth at the rate of a 
million ofmilesaday.it would take it forty-three thousand, three hundred years 
to reach the earth ; or, if the Almighty we're now to blot it out of the heavens, its 
brilliance would continue undiminished in our hemisphere for the space of three 
years. 

The most brilliant stars, till recently, were supposed to be 
situated nearest the earth, but later observations prove that 
this opinion is not well founded, since some of the smaller 
stars appear to have, not only a greater annual parallax, but 
an absolute motion in space, much greater than those of the 
brightest class. 

What conclusion may be drawn from this fact in regard :o the distances of the fixed 
stars' If the annual parallax of a star were knawn, by what simple rule could you 
compute its distance' If we allow the annual parallax of the nearest star to he l'' 
what will its distance be » What is aviean of lhe calculations of different astronomers 
for a paraslax of I'' ' What recent observations indicate a greater parallax to sent, 
of tlie searsi If the. parallax of Sirius be 1''.24, what will be its distance) Uoio lor.% 
would n require, passing through this distance, at the rate of a million of wiles a da± 
to reach the earth, and how long would its light continue undiminished to lit. wer 
it to be blotted from the heavens ? What has been supposed to be the relative distanc 
of the most brilliant stars from the eanh ? What do later •bservations prove, in regan 
to this opinion .» 



ECONOMY OF THE STARS. 157 

It has been computed that the light of Sirius, although 
twenty thousand million times less than that of our sun, is 
nevertheless, three hundred and twenty-four times greater 
than that of a star of the sixth magnitude. If we suppose 
the two stars to be really of the same size, it is easy to show 
that the star of the sixth magnitude is fifty-seven and one 
third times farther from us than Sirius is, because light dimin- 
ishes as the square of the distance of the luminous body in- 
creases. 

By the same reasoning it may be shown, that if Sirius were placed where the 
sun is, it would appear to us to be four times as large as the sun, and give four 
times as much light and heat. Ii is by no means unreasonable to suppose, that 
many of the fixed stars exceed a million of miles in diameter. 

We may pretty safely affirm, then, that stars of the sixth 
magnitude are not less than 900 millions of millions of miles 
distant from us ; or a million of times farther from us than 
the planet Saturn, which is scarcely visible to the naked eye. 
But the human mind in its present state, can no more appre- 
ciate such distances than it can infinity; for if our earth, 
which moves at more Chan the inconceivable velocity of a 
million and a half of miles a day, were to be hurried from its 
orbit, and to take the same rapid flight over this immense 
tract, it would not traverse it in sixteen hundred, thousand 
years; and every ray of light, although it moves at the rate 
of one hundred and ninety-three thousand miies in a single 
second of time, is more than one hundred and seventy years 
in coming from the star to us. 

But what is even this, compared with that measureless 
extent which the discoveries of the telescope indicate ? Ac- 
cording to Dr. Herschel, the light of some of the nebulae, 
just perceptible through his 40 feet telescope, must have been 
a million of ages in coming to the earth; and should any 
of them be now destroyed, they would continue to be percep- 
tible for a million of ages to come. 

Dr. Herschel informs us. that the glass which. he used would separate stars 
at 497 times the distance of Sirius. 

It is one of the wonders of creation that any phenomena 
of bodies at such an immense distance from us shoufd be 
perceptible by human sight ; but it is a part of the Divine 
Maker's plan, that although they do not act physically upon 
us, yet they should sp far be objects of our perception, as 

Sup;>o-e the light of Sirius to be twenty thousand million times less than that of our 
■un, bow would it conioare with that of a star of toe sixth magnitude ! If we suppose 
the two stars to k- at the same size, how much farther otV is the star of the sixth mag- 
nitude, than .-Mrius is ■ Suppose Sirtus to be placed where our sun is. how would it» 
apparent magnitwle, and its light and heat connate with those of the sun ! What may 
we generally urhrni of the distance of star^ of the sixth magnitude ! Can the human 
mind appreciate such distances ) What illustrations can you rive to show their im- 
mensity ! What is this distance compared with that of the telescopic stars, and the 
nebula; ? Why tus we abie to see bodies at so great a distance .» 

14 



158 NUMBER, DISTANCE. AND 

to expand our ideas of the vastness of the universe, and oi 
the stupendous extent and operations of his omnipotence. ' 

" With these facts before us," says an eminent astronomer 
and divine, " it is most reasonable to conclude, that those ex- 
pressions in the Mosaic history of Creation, which relate to 
the creation of the fixed stars, are not to be understood as 
referring to the time when they were brought into existence, 
as if they had been created about the same time with our 
earth ; but as simply declaring the fact, that, at whatever 
period in duration they were created, they derived their ex- 
istertce from GodP 

"That the stars here mentioned." (Gen. i. 16,) says a dis- 
tinguished commentator,* ' : were the planets of our system, 
and not the fixed stars, seems a just inference from the fact, 
that after mentioning them, Moses immediately subjoins, 
• And Elohim set them in the firmament of the heaven to 
give light upon the earth, and to rule over the day and over 
the night ;' evidently alluding to Venus and Jupiter, which 
are alternately our morning and evening stars, and which 
' give light upon the earth,' far surpassing in brilliancy any 
of the fixed stars." 

However vast the universe now appears, however numerous the worlds 
which may exist within its boundless ransie, the language of Scripture, and 
Scripture ulone, is sufficiently comprehensive and sublime, to express all ihe 
emotions which naturally arise in the mind, when contemplating its structure. 
This shows not only the harmony which subsists between the discoveries of 
the Revelation and the discoveries of Science, but also forms, by itself, a strong 
presumptive evidence, that the records of the Bible are authentic and divine. 

We have hitherto described the stars as being immovable 
and at rest ; but from a series of observations on double stars, 
Dr. Herschel found that a great many of them have changed 
their situations with regard to each other ; that some perform 
revolutions about others, at known and regular periods, and 
that the motion of some is direct, while that of others is ret- 
rograde ; and that many of them have dark spots upon their 
surface, and turn on their axis, like the sun. 

A remarkable change appears to be gradually taking place 
in the relative distances of the stars from each other in the 
con'stellation Hercules. The stars in tins region appear to 
be spreading farther and farther apart, while, those in the 
opposite point of the heavens seem to close nearer and nearer 
together, in the same manner as when walking through a 

* S. Turner, F. S. A. R. A. S. L., 1832. 

With these facts before us, what may we reasonably conclude with regard to the 
expressions in the Mosaic hi.-tory w h eh relate to thecreation of the fixed stars? Wlut 
it the opinion of Air. Turner in regard to the stars here mentioned ?- To what is the 
expression " To rule over the day aixl over the uijrht," supposed to allude? Give some 
of the real motions of the iixed stars. What remarkable change* are takin? 
place in the constellation h. 



ECONOMY OF THE STARS. 159 

forest, the trees toward which we advance, appear to be 
constantly separating, while the distance between those 
which we leave behind, is gradually contracting. 

From this appearance it is concluded, that the sun, with 
all its retinue of planetary worlds, is moving through the re- 
gions of the universe, toward some distant center, or around 
some wide, circumference, at the rate of sixty or seventy 
thousand miles an hour ; and that it is therefore highly prob- 
able, if not absolutely certain, that we shall never occupy 
that portion of absolute space, through which we are at this 
moment passing, during all the succeeding ages of eternity.* 

The author of the Christian Philosopher endeavors to 
convey some idea of the boundless extent of the universe, 
by the following sublime illustration : — 

" Suppose that one of the highest order of intelligences is 
endowed with a power of rapid motion superior to that of 
light, and with a corresponding degree of intellectual energy ; 
that he has been flying without intermission, from one pro- 
vince of creation to another, for six thousand years, and will 
continue the same rapid course for a thousand million years 
to come, it is highly probable, if not absolutely certain, that, at 
the end of this vast tour, he would have advanced no farther 
than the ' suburbs of creation,' — and that all the magnificent 
systems of material and intellectual beings he had surveyed, 
during his rapid flight, and for such a length of ages, bear 
no more proportion to the whole empire of Omnipotence, 
than the smallest grain of sand does to all the particles of 
matter contained in ten thousand worlds." 

Were a seraph, in prosecuting the tour of creation in the 
manner now stated, ever to arrive at a. limit beyond which 
no farther displays of the Divinity could be perceived, the 
thought would overwhelm his faculties with unutterable emo- 
tions ; he would feel' that he had now, in some measure, 
comprehended all the plans and operations of Omnipotence, 
and that no farther manifestation of the Divine glory re- 
mained to be explored. But we may rest assured that this 
can never happen in the case of any created intelligence. 

There is moreover an argument derivable from the laws of the physical 
worlil. that seems to strengthen, I hail almost said, to confirm, this idea 6f the 
Infinity of the material universe. It is this — If the number of stars be finite, 
and occupy only a part of space, the outward stars would be continually attracted 

* Professor Bessel does not fall in with this prevailing opinion. 

What conclusion is drawn from this appearance? Shall we then probably ever oc- 
cupy Hi it portion of space through which we are now passim; again? What illus- 
tration does the author of the Christian Philosopher give in order to convey some idea 
ol the boundless extent of the universe Were a seraph ever to arrive at a limit be- 
ypnd which no farther displays of the divine glory could be perceived, how would the 
idea allect him ' Is it nr.ibable that such a place exists m the universe, or within the 
scope of any created intelligence i 



160 FALLING, OR SHOOTING STARS. 

to those within, and in time would unite in one. But if the number be infinite, 
and they occupy an infinite space, all parts would be nearly in equilibno, and 
consequently each fixed star, being equally attracted in every directum, would 
keep its place. 

No wonder, then, that the Psalmist was so affected with 
the idea of the immensity of the universe, that he seems ;il 
most afraid lest he should be overlooked amidst the immen- 
sity of beings that must needs be under the superintendence 
of God ; or that any finite mortal should exclaim, when con- 
templating the heavens—" What is man, that THOU art 
mindfrl of him !" 



CHAPTER XVII. 

PALLING, OR SHOOTING STARS. 

The phenomenon of shooting star3, as it is called, is com- 
mon to all parts of the earth ; but is most frequently seen 
in tropical regions. The unerring aim, the startling velocity, 
and vivid brightness with which they seem to dart athwart 
the sky, and as suddenly expire, excite our admiration ; and 
we often ask, "What can they be?" 

But frequent as they are, this interesting phenomenon is 
not well understood. Some imagine that they are occasioned 
by electricity, and others, that they are nothing but luminous 
gas. Others again have supposed, that some of them are 
luminous bodies which accompany the earth in its revolution 
around the sun, and that their return to certain places might 
be calculated with as much certainty and exactness as that 
of any of the comets. 

Dr. Barney of Gosport, kept a record of all that he observ- 
ed in the course of several years. The number which he 
noticed in 1819, was 121, and in 1820, he saw 131. Profes- 
sor Green is confident that a much larger number are annu- 
ally seen in the United States. 

Signior Baccaria supposed they were occasioned by elec- 
tricity, and thinks this opinion is confirmed by the following 
observations. About an hour after sunset, he and some 
friends, that were with him, observed a falling star directing 
its course directly toward them, and apparently growing 
larger and larger, but just before it reached them it disap- 

Where does the phenomenon of falling, or shooting stare occur? What is there to 
excite our admiration in this phenomenon? Is this interesting phenomenon well un- 
derstood ? What are the different opinions in regard to them ? How many shooting 
stars did Dr. Burney observe in the years 1819 and 1820? Is it probable that a much 
larger number is seen every year in the United Stales 1 What did Baccaria suppose 
they were occasioned by, and what observations did he make to strengthen his 
ooinion ! 



FALLING, OR. SHOOTING STARS. 16 1 

peared. On vanishing, their faces, hands, and clothes, with 
the earth and all the neighboring objects, became suddenly 
illuminated with a diffused and lambent light. It was attend- 
ed with no noise. During their surprise at this appearance, 
a servant informed them, that he had seen a light shine sud- 
denly in the garden, and especially upon the streams which 
he was throwing to water it. 

The Signior also observed a quantity of electric matter 
collect about his kite, which had very much the appearance 
of a falling star. Sometimes he saw a kind of halo accom- 
panying the kite, as it changed its place, leaving some glim- 
mering of light in the place it had quitted. 

Shooting stars have been supposed by those meteorologists 
who refer them to electricity or luminous gas, to prognosticate 
changes in the weather, such as rain, wind, &c. ; and there 
is, perhaps, some truth in this opinion. The duration of the 
brilliant tract which they leave behind them, in their motion 
through the air, will probably be found to be longer or short- 
er, according as watery vapor abounds in the atmosphere. 

The notion that this phenomenon betokens high winds, is 
of great antiquity. Virgil, in the first book of his Georgics, 
expresses the same idea : — 

" Ssepe etiam stellas vento impendente videbis 
Pracipites coelo labi ; noctisque per umbram 
Flammarum longos a tergo aibescere tractus. 

And oft, before tempestuous winds arise, 
The seeming stars fall headlong from the skies, 
And shooting through the darkness, gild the night 
With sweeping glories and long trails of light." 

The number of shooting stars, observed in a single night, 
though variable, is commonly very small. There are, how- 
ever, several instances on record of their falling in " showers " 
— when every star in the firmament seems loosened from its 
sphere, and moving in lawless flight from one end of the 
heavens to the other. As early as the year 472, in the month 
of November, a phenomenon of this kind took place near 
Constantinople. As Theophanes relates, " the sky appeared 
to be on fire," with the coruscations of the flying meteors. 

A shower of stars, exactly similar took place in Canada, between the 3d and 
4th of July, 1814, and another at Montreal, in November, 1819. In all these cases, 
a residuum, or black dust, was deposited upon the surface ol the waters, and upon 
the roofs of buildings, and other objects. In the year 1810, '•inflamed sub- 
stances," it is said, fell into and around lake Van, in Armenia, which stained the 
water of a blood color, and cleft the earth in various places. On the 5th ol 

What was the appearance upon streams of water ? What did he observe at this time 
> about his kite ? What connection are they supposed to have with meteorology? What 
circumstance may we probably find to confirm this idea? Is this notion of very an- 
cient, or modern date ? What is, usually, the number of shooting stars observed in a 
single night > When, and where, occurred the first instance, on record, of their tailing 
in great numbers? Mention some other instances. What remarkable vestige too* 
left by these meteoric showers .' 

14* 



162 FALLING. OR SHOOTING STARS. 

September, 1819, a like phenomenon was seen in Moravia. History furnishes 
many more instances of meteoric showers, depositing a red dust in some places, 
bo plentiful as to admit of chemical analysis. 

The commissioner, (Mr. Andrew Ellicott,) who was sent 
out by our government to fix the boundary between the Span- 
ish possessions in North America and the United States, wit- 
nessed a very extraordinary flight of shooting stars, which 
filled the whole atmosphere from Cape Florida to the West 
India Islands. This grand phenomenon took place the 12th 
of November, 1799, and is thus described : — u I was called up," 
says Mr. Ellicott, " about 3 o'clock in the morning, to see the 
shooting stars, as they are called. The phenomenon was 
grand and awful. The whole heavens appeared as if illu- 
minated with sky-rockets, which disappeared only by the light 
of the sun, after daybreak. The meteors, which at any one 
instant of time, appeared as numerous as the stars, flew in 
all possible directions except from the earth, toward which 
they all inclined more or less, and some of them descended 
perpendicularly over the vessel we were in. so that I was in 
constant expectation of their falling on us." 

Mr. Ellicott further states that his thermometer, which had 
been at 80° Fahr. for the four days preceding, fell to 56° 
about 4 o clock, A. M., and that nearly at the same time, the 
wind changed from the south to the north-west, from whence it 
blew with great violence for three days without intermission. 

These same appearances were observed, the same night, 
at Santa Fe de Bogota, Cumana, Q,uito, and Peru, in South 
America ; and as far north as Labrador and Greenland, ex- 
tending to Weimar in Germany, being thus visible over an 
extent on the globe of 64° of latitude, and 94° of longitude. 

The celebrated Humboldt, accompanied by M. Bompland, then in S. America, 
thus speaks of the phenomenon :— "Toward the morning of the 13th of No- 
vember, 1799, we witnessed a most extraordinary scene of shooting meteors. 
Thousands of bolides, and falling stars succeeded each other during four hours. 
Their direction was very regular from north to south. From the beginning of 
the phenomenon there was not a space in the firmament, equal in extent to 
three diameters of the moon, which was not filled every instant with bolides or 
falling stars. All the meteors left luminous traces, or phosphorescent bands 
behind them, which lasted seven or eight seconds." 

This phenomenon was witnessed by the Capuchin missionary at San Fer- 
nando de Afiura, a village situated in lat. 7° 53' 12", amidst the savannahs of the 
province of Varinas ; by the Franciscan monks stationed near the cataracts of 
the Oronoco, and at Marca, on the banks of the Rio Negro, lat. 2° 40", long 
70° 21', and in the west of Brazil, as far as the equator itself; and also at the 
city of Porto Cabello, lat. 10° 6' 52", in French Guiana, Popayan, Quito, and 
Peru. It is somewhat surprising that the same appearances, observed in places 
so widely separated, amid the vast and lonely deserts of South America, should 
have been seen, the same night, in the United States, in Labrador, in Greenland, 
and at Itterstadt, near Weimar, in Germany ! 

Recite instances o£ a similar kind, in which a red dust has been deposited. Describe 
the phenomenon of shooting stars described by Mr. Ellicott, in 1799. Describe the 
same phenomenon as seen, in South America, bij Humboldt and others. In what otlier 
parts of the earth was it loitnessed, and by whom ? 



PALLING, OR SHOOTING STARS. 163 

We are told that thirty years before, at the city of Quito, 
" there was seen in one part of the sky, above the volcano 
of Cayamburo, so great a number of falling stars, that the 
mountain was thought to be in flames. This singular sight 
lasted more than an hour. The people assembled in the 
plain of Exida, where a magnificent view presents itself of 
the highest summits of the Cordilleras. A procession was 
already on the point of setting out from the convent of St 
Francis, when it was perceived that the blaze on the horizon 
was caused by fiery meteors, which ran along the sky in all 
directions, at the altitude of 12 or 13 degrees." 

But the most sublime phenomenon of shooting stars, of 
which the world has furnished any record, was witnessed 
throughout the United States on the morning of the 13th of 
November, 1833. 

The entire extent of this astonishing exhibition has not 
been precisely ascertained, but it covered no inconsiderable 
portion of the earth's surface. It has been traced from the 
longitude of 61°. in the Atlantic ocean, to longitude 100° in 
Central Mexico, and from the North American lakes to the 
West Indies. 

It was not seen, however, any where in Europe, nor in South America, nor in 
any part of the Pacific ocean yet heard from. 

Every where, within the limits above mentioned, the first 
appearance was that of fireworks of the most imposing gran- 
deur, covering the entire vault of heaven with myriads of 
fire-balls, resembling sky-rockets. Their coruscations were 
bright, gleaming and incessant, and they fell thick as the 
flakes in the early snows of December. To the splendors 
of this celestial exhibition, the most brilliant sky-rockets and 
fireworks of art, bear less relation than the twinkling of the 
most tiny star to the broad glare of the sun. The whole 
heavens seemed in motion, and suggested to some the awful 
grandeur of the image employed in the apocalypse, upon the 
opening of the sixth seal, when "the stars of heaven fell 
unto the earth, even as a fig-tree casteth her untimely figs, 
when she is shaken of a mighty wind." 

One of the most remarkable circumstances attending this 
display was, that the meteors all seemed to emanate from one 
and the same point, a little south-east of the zenith. Following 
ihe arch of the sky, they ran along with immense velocity 

Describe another phenomenon of a similar kind, seen in South America about thirty 
years before? When occurred the most sublime phenomenon^!* shooting stars of 
which the world has any record? How extensively was it witnessed? What was 
the first appearance of the phenomenon? What scene in the apocalypse did it sug- 
gest to some? From what point did the meteors appear to emanate ? Describe their 
motion . 



164 FALLING, OR SHOOTING STARS. 

describing, in some instances, an arc of 30° or 40° in a few 
seconds. 

On more attentive inspection it was seen, that the meteors 
exhibited three distinct varieties ; the first, consisting of 
phosphoric lines, apparently described by a point ; the second, 
of large fire-balls, that at intervals darted along the sky. leav- 
ing luminous trains, which occasionally remained in view for 
a number of minutes, and, in some cases, for half an hour or 
more ; the third, of undefined luminous bodies, which remain- 
ed nearly stationary in ihe heavens for a long time. 

Those of the first variety were the most numerous, and 
resembled a shower of fiery snow driven with inconceivable 
velocity to the north of west. The second kind appeared 
more like falling stars — a spectacle which was contemplated 
by the more unenlightened beholders with great amazement 
and terror. The trains which they left were commonly 
white, but sometimes were tinged with various prismatic 
colors, of great beauty. 

These fire-balls were occasionally of enormous size. Dr. 
Smith, of North Carolina, describes one which appeared lar- 
ger than the full moon rising.* <; I was," says he, ''startled 
by the splendid light in which the surrounding scene was 
exhibited, rendering even small objects quite visible." The 
same ball, or a similar one, seen at New Haven, passed off in 
a north-west direction, and exploded a little northward of the 
star Capella, leaving, just behind the place of explosion, a 
train of peculiar beauty. The line of direction was at first 
nearly straight ; but it soon began to contract in length, to 
dilate in breadth, and to assume the figure of a serpent 
scrolling itself up, until it appeared like a luminous cloud 
of vapor, floating gracefully in the air, where it remained 
in full view for several minutes. 

Of the third variety of meteors, the following are remark- 
able examples : — At Poland, Ohio, a luminous body was dis- 
tinctly visible in the north-east for more than an hour. It was 
very brilliant, in the form of a pruning-hook, and apparently 
twenty feet long, and eighteen inches broad. It gradually 

* If this body were at the distance of no mile3 from the observer, it must have had 
a diameter of one mile ; if at the distance of U miles, its diameter waa 52S teet: and 
if only one mile off, it must have been 4S feet in diameter. These considerations leave 
no doubt that many of the meteors were bodies of large size. 

What other appearances were observed upon more attentive inspection? Give a 
more particular account of the first variety. 01" the second. What do we know in re- 
gard to the size of these fire-bails ? How does Dr. Smith describe one seen by him in 
North Carolina? What was the appearance of the same or a similar ball, as seen at 
New Haven? What was there peculiar in the course, and final disappearance of it? 
Suppose this meteor was no miles distant from the place of observation, what must 
have been its diameter ? What, if it were 11 miles distant? What, if only one milel 
Mention some examples of the third variety of meteors. 



FALLING, OR SHOOTING STARS. 165 

settled toward the horizon, until it disappeared. At Niagara 
Falls, a large, luminous body, shaped like a square table, 
was seen near the zenith, remaining for some time almost 
stationary, emitting large streams of light. 

The point from which the meteors seemed to emanate, 
was observed, by those who fixed its position among the stars, 
to be in the constellation Leo ; and, according to their con- 
current testimony, this radiant point was stationary among 
the stars, during the whole period of observation ; that is, it 
did not move along with the earth, in its diurnal revolution 
eastward, but accompanied the stars in their apparent pro- 
gress westward. 

A remarkable change of weather from warm to cold, ac- 
companied the meteoric shower, or immediately followed it. 
In all parts of the United States, this change was remarkable 
for its suddenness and intensity. In many places, the day 
preceding had been unusually warm for the season, but. be- 
fore the next morning, a severe frost ensued, unparalleled, for 
the time of year. 

In attempting to explain these mysterious phenomena, it is 
argued, in the first place, that the meteors had their origin 
beyond the limits of our atmosphere ; that they of course did 
not belong to this eanh, but to the regions of space exterior 
to it. 

The reason on which this conclusion is founded is this : — All bodies near the 
earth, including the atmosphere itself, have a common motion with the earth 
around its axis from west to east; but the radiant point, that indicated the 
source from which the meteors emanated, followed the course of the stars 
from east to west ; therefore, it was independent of the earth's rotation, and con- 
sequently, at a great distance from it, and beyond the limits of the atmosphere. 
The height of the meteoric cloud, or radiant point, above the earth's surface, was, 
according to the mean average of Professor Olmsted's observations, not less 
than 2238 miles. 

That the meteors were constituted of very light, combus 
tible materials, seems to be evident, from their exhibiting the 
actual phenomena of combustion, they being consumed, or 
converted into smoke, with intense light; and the extreme 
tenuity of the substance composing them is inferred from the 
fact that they were stopped by the resistance of the air. Had 
theL- quantity of matter been considerable, with so prodigious 
a velocity, they would have had sufficient momentum to dash 
them upon the earth ; where the most disastrous consequences 
might have followed. 

In what constellation was the point from which the meteors seemed to radiate? 
What changes were observed in the weather during or soon after this phenomenon ? 
In attempting to account for these phenomena, what hypothesis has been advanced 
in regard to the place where the meteors had their origin ? What is the reasoning by 
which this hypothesis is sustained/ How high teas the meteoric cloud supposed to be 
above the earth ! What do we know in regard to the substance of which the meteors 
were composed ? What might have been the consequences, if their quantity ot matter 
taad been considerable ? 



166 FALLING, OE. SHOOTING STARS. 

The momentum of even light bodies of such size, and in such numbers, tra- 
versing the atmosphere with such astonishing velocity, must have produced ex- 
tensive derangements in the atmospheric equilibrium. Cold air from the upper 
regions would be brought down to the earth ; the portions of air incumbent over 
districts of country remote from each other, being mutually displaced, would 
exchange places, the air of the warm latitudes be transferred to colder, ami that 
of cold latitudes to warmer regions. 

Various hypotheses have been proposed to account for this 
wonderful phenomena. The agent which most readily sug- 
gests itself in this, and in many other unexplained natural 
appearances, is electricity. But no known properties of 
electricity are adequate to account for the production of the 
meteors, for the motions, or for the trains which they, in many 
instances, left behind them. Others, again, have referred their 
proximate cause to magnetism, and to phospho retted hydro- 
gen ; both of which, however, seem to be utterly insufficient, 
so far as their properties are known, to account for so unu- 
sual a phenomenon. 

Professor Olmsted, of Yale College, who has taken much 
pains to collect facts, and to establish a permanent theory 
for the periodical recurrence of such phenomena, came to 
the conclusion, that — 

The meteors of November 13th. 1833, emanated from a 
nebulous body, which was then pursuing its way along with 
the earth around the sun; that this body continues to revolve 
around the sun, in an elliptical orbit — but little inclined to 
the plane of the ecliptic, and having its aphelion near the 
orbit of the earth; and finally , that the body has a period 
of nearly six months, and that its perihelion is a little below 
the orbit of Mercury. 

This theory at least accommodates itself to the remarkable 
fact, that almost all the phenomena of this description, which 
are known to have happened, have occurred in the two op- 
posite months of April and November. A similar exhibition 
of meteors to that of November, 1833, was observed on the 
same day of the week, April 20th, 1S03, at Richmond, in Vir- 
ginia, Stockbridge, Massachusetts, and at Halifax, in British 
America. Another was witnessed in the autumn of 1818, in 
the North Sea, when, in the language of the observers, c: all 
the surrounding atmosphere was enveloped in one expansive 
sea of fire, exhibiting the appearance of another Moscow in 
flames." 

Exactly one year previous to the great phenomenon of 
1833, namely, on the 12th of November, 1832, a similar me- 

What effect must the momentum of even light bodies of such size, moving loith such 
velocity, have had upon the atmosphere? Mention some hypotheses w hich have been 
proposed to accoun for these meteors. To what conclusion did Professor Olmsted, 
after a long investigation, come, in rei'nrd to them ? To what remarkable facts in such 
phenomena, is this theory adapted ? At what other corresponding periods have similar 
phenomena been observed ? 



FALLING, OR. SHOOTING STARS. 167 

teonc display was seen near Mocha, on the Bed Sea, by 
Capt Hammond and crew, of the ship Restitution. 

A gentleman in South Carolina thus describes the effect of the phenomenon 
of 1833 upon his ignorant blacks: — "I was suddenly awakened by the most 
distressing cries that ever fell on my ears. Shrieks of horror, and cries of 
mercy, I could hear from most of the negroes of three plantations, amounting 
in all to about six or eight hundred. While earnestly listening for the cause, 
I heard a faint voice near the door calling my name ; I arose, and taking my 
sword, stood at the door. At this moment, I heard the same voice still be- 
seeching me to rise, and saying, 'O! my God, the world is on fire!' I then 
opened the door, and it is difficult to say which excited me most— the awful- 
ness of the scene, or the distressed cries of the negroes ; upward of one hun- 
dred lay prostrate on the ground — some speechless, and some with the bit- 
terest cries, but most with their hands raised, imploring God to save the world 
and them. The scene was truly awful ; for never did rain fall much thicker, 
than the meteors fell toward the earth; east, west, north, and south, it was the 
same!" 



Since the preceding went to press, the author has been po 
litely furnished, by Professor Olmsted, with the accom- 
panying communication. 

" I am happy to hear that you propose to stereotype 
your ' G-eography of the Heavens.' It has done much, I 
believe, to diffuse a popular knowledge of astronomy, and 
I am pleased that your efforts are rewarded by an ex* 
tended patronage. 

" Were I now to express my views on the subject (Me- 
teoric Showers) in as condensed a form as possible, I should 
state them in some such terms as the following : The mete- 
oric showers which have occurred for several years past on 
or about the 13th of November, are characterized by four 
peculiarities, which distinguished them from ordinary 
shooting stars. First, they are far more numerous than 
common, and are larger and brighter. Secondly, they are 
in much greater proportion than usual, accompanied by 
luminous trains. Thirdly, they mostly appear to radiate 
from a common center ; that is, were their paths in the 
heavens traced backward, they would meet in the same 
part of the heavens : this point has for three years past, 
at least, been situated in the constellation Leo. Fourthly, 
the greatest display is every where at nearly the same 
time of night namely, from three to four o'clock — a time 



68 FALLING, OR SHOOTING STARS. 

about half-way from midnight to sunrise. The meteors 
are inferred to consist of combustible matter, because they 
are seen to take fire and burn in the atmosphere. They 
are known to be very light, because, although they fall 
toward the earth with immense velocity, few, if any, ever 
reach the earth, but are arrested by the air, like a wad 
fired from a piece of artillery. Some of them are inferred 
to be bodies of comparatively great size, amounting in di- 
ameter to several hundred feet, at least, because they are 
seen under so large an angle, while they are at a great dis- 
tance from the spectator. Innumerable small bodies, thus 
consisting of extremely light, thin, combustible matter, 
existing together in space far beyond the limits of the at- 
mosphere, are believed to compose a body of immense 
extent, which has been called ' the nebulous body.' Only 
the skirts or extreme portions of this are brought down to 
the earth, while the entire extent occupies many thousand, 
and perhaps several millions of miles. This nebulous body 
is inferred to have a revolution around the sun, as well as 
the earth, and to come very near to the latter about the 
13th of November each year. This annual meeting every 
year, for several years in succession, could not take place 
unless the periodic time of the nebulous body is either 
nearly a year, or half a year. Various reasons have in- 
duced the belief that half a year is the true period ; but 
this point is considered as somewhat doubtful. The zodi- 
acal light, a faint light that appears at different seasons of 
the year, either immediately preceding the morning or 
following the evening twilight, ascending from the sun in 
a triangular form, is, with some degree of probability, 
thought to be the nebular body itself, although the exist- 
ence of such a body, revolving in the solar system, was 
inferred to be the cause of the meteoric showers, before 
any connection of it with the zodiacal light was even 
thought of." 



GENERAL PHENOMENA 



SOLAR SYSTEM, 



CHAPTER XVIII. 

Our attention has hitherto been directed to those bo ties 
which we see scattered every where throughout the whole 
celestial concave. These bodies, as has been shown, twinkle 
with a reddish and variable light, and appear to have always 
the same position with regard to each other. We know 
that their number is very great, and that their distance from 
us is immeasurable. We are also acquainted wilh their 
comparative brightness and their situation. In a word, we 
have before us their few visible appearances, to which our 
knowledge of them is well nigh limited ; almost all our rea- 
sonings in regard to them being founded on comparatively 
few and uncertain analogies. Accordingly, our chief busi- 
ness thus far has been to detail their number, to describe 
their brightness and positions, and to give the names by 
which they have been designated. 

There now remain to be considered certain other celes- 
tial bodies, all of which, from their remarkable appearance 
and changes, and some of them from their intimate con- 
nection with the comfort, convenience, and even existence 
of man, must have always attracted especial observation, 
and been objects of the most intense contemplation and 
the deepest interest. Most of these bodies are situated 
within the limits of the Zodiac. The most important, of 
them are, the Sun. so superior to all the heavenly bo lies 
for its apparent magnitude, for the light and heat which 
it imparts, for the marked effects of its changes of position 
with regard to Uie Earth ; and the Moon, so conspicuous 
among the bodies which give light by night, and from 
her soft, and silvery brightness, so pleasing to behold ; iv- 

To whit particulars h our knowledge of the fixed stars, those heavenly bo-lies which 
we have ht;.e:orbre hern oo'isidemu.', well 1112I1 confi'ied • Whereare the bodies winch 
now remain to be considered situated? Which of them are ihe most important I 

15 



170 GENERAL PHENOMENA 

markable not only for changes of position, but for the 
varied phases or appearances which she presents, as she 
waxes from her crescent form through all her different 
stages of increase to a full orb, and wanes back again to 
her former diminished figure. • 

The partial or total obscuration of these two bodies, which 
sometimes occurs, darkness taking place even at mid -day, 
and the face of night, before lighted up by the Moon's beams, 
being suddenly shaded by their absence, have always been 
among the most striking astronomical phenomena, and so 
powerful in their influence upon the beholders, as to fill them 
with perplexity and fear. If we observe these two bodies, 
we shall find that, besides their apparent diurnal motion 
across the heavens, they exhibit other phenomena, which 
must be the effect of motion. The Sun during one part of 
the year will be seen to rise every day farther and farther 
toward the north, to continue longer and longer above the 
horizon, to be more and more elevated at mid-day, until he 
arrives at a certain limit ; and then, during the other part, 
the order is entirely reversed. The Moon sometimes is not 
seen at all; and then, when she first becomes visible, ap- 
pears in the west, not far from the setting Sun, with a slen- 
der crescent form ; every night she appears at a greater 
distance from the setting Sun, increasing in siz.e, until at 
length she is found in the east, just as the Sun is sinking 
below the horizon in the west. 

The Sun, if his motions be attentively observed, will be 
found to have another motion, opposite to his apparent diur- 
nal motion from east to west. This maybe perceived dis- 
tinctly, if we notice, on any clear evening, any bright star 
which is first visible after sunset, near the place where he 
sunk below the horizon. The following evening, the star 
will not be visible on account of the approach of the Sun, 
and all the stars on the east of it will be successively eclipsed 
by his rays, until he shall have made a complete apparent 
revolution in the heavens. These are the most obvious 
phenomena exhibited by these two bodies. 

There are also situated within the limits of the Zodiac 
certain other bodies, which, at first view and on a superficial 
examination, are scarcely distinguishable from the fixed 
stars. But, observed more attentively, they will be seen to 
shine with a milder and steadier light, and, besides being 
carried round with the stars, in the apparent revolution of 
the great celestial concave, they will seem to change their 



Describe the most obvious r h*nomena of the Sun and Moon. Describe the most 
obvious phenomena of the planets. 



OF THE SOLAR SYSTEM. 171 

places in the concave itself. Sometimes they are station- 
ary ; sometimes they appear to be moving from west to east, 
and sometimes to be going back again from east to west : 
being seen at sunset sometimes in the east, and sometimes 
in the west, and always apparently changing their position 
with regard to the earth, each other, and the other heaven- 
ly bodies. From their wandering, as it were, in this man- 
ner through the heavens, they were called by the Greeks 
ir\avr)TJt, planets, which signifies wanderers. 

There also sometimes appear in the heavens bodies of a 
very extraordinary aspect, which continue visible for a con- 
siderable period, and then disappear from our view ; and 
nothing more is seen of them, it may be, for years, when they 
again present themselves, and take their place among the 
bodies of the celestial sphere. They are distinguished from 
the planets by a dull and cloudy appearance, and by a train 
of light. As they approach the sun, however, their faint and 
nebulous light becomes more and more brilliant, and their 
train increases in length, until they arrive at their nearest 
point of approximation, when they shine with their greatest 
brilliancy. As they recede from the Sun, they gradually 
lose their splendor, resume their faint and nebulous appear- 
ance, and their train diminishes, until they entirely disappear. 
They have no well-defined figure : they seem to move in 
every possible direction, and are found in every part of the 
heavens. From their train, they were called by the Greeks 
KOfirjrat, comets, which signifies having long hair. 

The causes of these various phenomena muet have early 
constituted a very natural subject of inquiry. Accordingly, 
we shall find, if we examine the history of the science, that 
in very early times there were many speculations upon this 
subject, and that different theories were adopted to account 
for these celestial appearances. 

The Egyptians, Chaldeans. Indians, and Chinese, early possessed many astro- 
nomical facts, many observations of important phenomena, and many rules and 
methods of astronomical calculation ; and it has been imagined, that they had 
the ruins of a great system of astronomical science, which, in the earliest ages 
of the world, had been earned to a great degree of perfection, and that while the 
principles and explanations of the phenomena were lost, the isolated, unconnect- 
ed facts, rules of calculation, and phenomena themselves, remained. Thus, the 
Chinese, who, it is generally agreed, possess the oldest authentic observations on 
record, have recorded in their annals, a conjunction of five planets at the same 
time, which happened 2461 years before Christ, or 100 years before the flood. 
By mathematical calculation, it is ascertained that this conjunction really occurred 
at that time. The first observation of a solar eclipse of which the world has any 
knowledge, was made by the Chinese. 2128 years before Christ, or 220 year's 
after the deluge. It seems, also, that the Chinese understood the method of cal- 
culating eclipses; for, it is said, that the emperor was so irritated against thf 

Whence do they derive their name ! Describe the comets. Whence is their name 
derived > Il7?ar oriental nations early possessed many important astronomical facts, 
observations, and rules ! Whence is it supposed Viat they obtained them ? 



172 GENERAL PHENOMENA 

great officers of state for neglecting to predict the eclipse, that he caused them 
to be put to death.* The astronomical epoch of tlie Chinese, according to Bailty, 
commenced with Fohi, their first emperor, who flourished 2992 years before the 
Christian era, or about 350 years before the deluge. If it be asked how the 
knowledge of this antediluvian astronomy was preserved and transmitted, it is 
said (hat the columns on which it was registered have survived the delude, and 
that those of E;rypt are only copies which have become originals, now that the 
others have been forgotten. The Indians, also, profess to have many celestial 
observations of a very early date. The Chaldeans have been justly celebrated 
in all ages for their astronomical observations. When Alexander took Babylon, 
his preceptor, Callisthenes, found a series of Chaldean observations, made in that 
city, and extending back, with little interruption, through a period of 1903 years 
preceding that event. This would carry us back to at least 2231 years before 
the birth of Christ, or to about the time of the dispersion of mankind by the con- 
fusion of tongues. Though it be conceded, that upon this whole period in the 
history of the science, the obscurity of very remote antiquity must necessari- 
ly rest, still it will remain evident that the phenomena of the heavenly bodies 
had been observed with great attention, and had been a subject of no ordinary 
interest. 

But however numerous or important were the observations of oriental an- 
tiquity, they were never reduced to the shape and symmetry of a regular 
Bysfem. 

The Greeks, in all probability, derived many notions in regard to this science, 
and many facts and observations, from Egypt, the <:reat fountain of ancient 
learning and wisdom, and many were the speculations and hypotheses of their 
philosophers. In the fabulous period of Grecian history, Atlas, Hercules, Linus, 
and Orpheus, are mentioned as persons distinguished for their knowledge of 
astronomy, and for the improvements which they made in the science. But in 
regard to" this period, little is known with certainty, and it must be considered, 
as it is termed, fabulous. 

The first of the Greek philosophers who taught Astronomy, 
was T hales, of Miletus. He flourished about 640 years be- 
fore the Christian era. Then followed Anaximander, Anax- 
imenes, Anaxagoras, Pythagoras. Plato. Some of the doc- 
trines maintained by these philosophers were, that the 
Earth was round, that it had two motions, a diurnal motion 
on its axis, and an annual motion around the Sun, that the 
Sun was a globe of fire, that the Moon received her light 
from the Sun, that she was habitable, contained mountains, 
seas, &c. ; that her eclipses were caused by the Earth's 
shadow, that the planets were not designed merely to adorn 
our heavens, that they were worlds of themselves, and that 
the fixed stars were centers of distant systems. Some of 
them, however, maintained, that the Earth was flat, and 
others, that, though round, it was at rest in the center of 
the universe. 

When that distinguished school of philosophy was estab- 
lished at Alexandria, in Egypt, by the munificence of the 

* It is well known that the Chinese have, from time immemorial, considered Solai 
Eclipses s nd conjunctions of the planets, as prognostics of importance to the Empire, 
and that they have been predicted as a matter of State policy. 

Give some instances. Were these facts, however, reduced to a science ? Whence, 
is it probable, that the Greeks derived their first notions of astronomy? What is the 
name of the first of the Greek philosophers who taurrht astronomy? At what time did 
he flourish ? What Greek philosophers after him taught upon the same subject i Men- 
Uon some of the doctrines which 'hey maintained. 



OF THE SOLAR SYSTEM. 173 

sovereigns to whom that portion of Alexander's empire had 
fallen, astronomy received a new impulse. It was now, in 
the second century after Christ, that the first complete sys- 
tem or treatise of astronomy of which we have any know- 
ledge, was formed. All before had been unconnected and 
incomplete. Ptolemy, with the opinions of all antiquity, 
and of all the philosophers who had preceded him, spread 
out before him, composed a work in thirteen books, called 
the MeyaXn Hwratjis, or Great System. Rejecting the doc- 
trine of Pythagoras, who taught that the Sun was the center 
of the universe, and that the Earth had a diurnal motion on 
its axis and an annual motion around the Sun, as contrary 
to the evidence of the senses, Ptolemy endeavored to ac- 
count for the celestial phenomena, by supposing the Earth 
to be the center of the universe, and all the heavenly bodies 
to revolve around it. He seems to have entertained an idea, 
in regard to the supposition, that the Earth revolved on its 
axis, similar to one which some entertain even at the pres- 
ent day. " If." says he, ' : there were any motion of the 
Earth common to it and all other heavenly bodies, it would 
certainly precede them all by the excess of its mass being 
so great; and animals and a certain portion of heavy bodies 
would be left behind, riding upon the air, and the Earth 
itself would very soon be completely carried out of the 
heavens." 

In explaining the celestial phenomena, however, upon his hypothesis, he 
met with a difficulty in the apparently stationary attitude and retrograde mo- 
tions which he saw the planets sometimes have. To explain this, "however, 
he supposed the planets to revolve in small circles which he called epicycles, 
which were, at the same time, carried around the Earth in larger circles, which 
he called deferents, or carrying circles. In following out his theory and apply- 
ing it to the explanation of different phenomena, it became necessary to add new 
epicycles, and to have recourse to other expedients, until the system became 
unwieldy, cumbrous, and complicated. This theory, although astronomical ob- 
servations continued to be made, and some distinguished astronomers appeared 
from time to time, was the prevailing theory until the middle of rhe 15th century. 
It was not, however, always received with implicit confidence; nor were ita 
difficulties always entirely unappreciated. 

Alphonso X., king of Castile, who flourished in the 13th century, when 
contemplating the doctrine of the epicycles, exclaimed, " Were the universe 
thus constructed, if the deity had called me to his councils at the creation of 
the world, I could have given him good advice." He did not, however, mean 
any impiety or irreverence, except what was directed against the system of 
Ptolemy. 

About the middle of the 15th century, Copernicus, a 
native of Thorn in Prussia, conceiving a passionate attach- 
ment to the study of astronomy, quitted the profession of 

When was the first complete system of Astronomy written, and by whom ? In how 
many books was it comprised, and what was the work called? What was the system 
ot Ptolemy ? How ditl Ptolemy explain the stations and retrogr ablations of the plan 
it* ? How long xcas the system of Ptolemy the prevailing system ? Was it ahcaxjs re- 
ceived with implicit confidence? Who established a new system of Astronomy about 
the middle ot the 15th century ? 

15* 



174 GENERAL PHENOMENA 

medicine, and devoted himself with the most intense ardor 
to the study of this science. "His mind," it is said, "had 
long been imbued with the idea that simplicity and harmony 
should characterize the arrangements of the planetary 
system. In the complication and disorder which he saw 
reigned in the hypothesis of Ptolemy, he perceived insuper- 
able objections to its being considered as a representation 
of nature." 

In the opinions of the Egyptian sages, in those of Pythag- 
oras, Philolaus, Aristarchus and Nicetas, he recognized his 
own earliest conviction that the Earth was not the center of 
the universe. His attention was much occupied with the 
speculation of Martinus Capella, who placed the Sun be- 
tween Mars and the Moon, and made Mercury and Venus 
revolve round him as a center, and with the system of Ap- 
pollonius Pergoeus who made all the planets revolve around 
the Sun, while the Sun and Moon were carried around the 
Earth in the center of the universe. 

The examination, however, of these hypotheses, gradual- 
ly expelled the difficulties with which the subject was beset, 
and after the labor of more than thirty years, he was per- 
mitted to see the true system of the universe. The Sun he 
considered as immovable, in the center of the system, 
while the Earth revolved around him, between the orbits of 
Venus and Mars, and produced by its rotation about its axis 
all the diurnal phenomena of the celestial sphere. The 
other planets he considered as revolving about the Sun, in 
orbits exterior to that of the Earth. ( See the Relative Po- 
sition of the Planets* Orbits, Plate I. of the Atlas.) 

Thus, the stations and retrogradations of the planets were 
the necessary consequence of their own motions, combined 
with that of the Earth about the Sun. He said that " by 
long observation, he discovered that, if the motions of the 
planets be compared with that of the Earth, and be estima- 
ted according to the times in which they perform their rev- 
olutions, not only their several appearances would follow 
from this hypothesis, but that it would so connect the order 
of the planets, their orbits, magnitudes, and distances, and 
even the apparent motion of the fixed stars, that it would 
be impossible to remove one of these bodies out of its place 
without disordering the rest, and even the whole of the uni- 
verse also." 

Soon after the death of Copernicus, arose Tycho Brahe, 

What led him to doubt the system of Ptolemy? How long was he employed in the 
examination of different hypotheses before he came to a satisfactory result' What 
was the system of Copernicus ? What distinguished astronomer, soon after the time 
•f Copernicus, enriched astronomy with many valuable observations » 



OF THE SOLAR SYSTEM. 175 

born at Knudstorp, in Norway, in 1546. Such was the 
distinction which he had attained as an astronomer, that 
when, dissatisfied with his residence in Denmark, he had re- 
. solved to remove, the King of Denmark, learning his inten- 
tions, detained him in the kingdom, by presenting him with 
the canonry of Rothschild, with an income of 2000 crowns 
per annum. He added to this sum a pension of 1000 crowns, 
gave him the island of Huen, and established for him an ob- 
servatory at an expense of about 200,000 crowns. Here 
Tycho continued, for twenty-one years, to enrich astronomy 
with his observations. His observations upon the Moon 
were important, and upon the planets, numerous and precise, 
and have formed the data of the present generalizations in 
astronomy. He, however, rejected the system of Coperni- 
cus ; considering the Earth as immovable in the center of the 
system, while the Sun, with all the planets and comets re- 
volving around him, performed his revolution around the 
earth, and, in the course of twenty-four hours, the stars also 
revolved about the central body. This theory was not as 
simple as that of Copernicus, and involved the absurdity of 
making the Sun, planets, &c, revolve around a body com- 
paratively insignificant. 

Near the close of the 15th century, arose two men, who 
wrought most important changes in the science, Kepler and 
Galileo, the former a German, the latter an Italian. 

Previous to Kepler, all investigations proceeded upon the 
supposition that the planets moved in circular orbits which 
had been a source of much error. This supposition Kepler 
showed to be false. He discovered that their orbits were 
ellipses. The orbits of their secondaries or moons he also 
found to he the same curve. He next determined the di- 
mensions of the orbits of the planets, and found to what 
their velocities in their motions through their orbits, and the 
times of their revolutions, were proportioned ; all truths of 
the greatest importance to the science. 

While Kepler was making these discoveries of facts, very 
essential for the explanation of many phenomena, Galileo 
was discovering wonders in the heavens never before seen 
by the eye of man. Having improved the telescope, and 
applied it to the heavens, he observed mountains and valleys 
upon the surface of our Moon ; satellites or secondaries 



What inducement; did the king of Denmark offer him to remain in the kingdom? 
How lone did he continue to make observations in his observatory in tin- island of 
Huen? How were the heavenly bodies arranged, in his system? What absurdity did 
it involve ? Whit two illustrious astronomers made several very important discoveries 
soon after the time of Tycho Brahe 1 What were the discoveries of Kepler ? What 
were the discoveries of Galileo ? 



176 GENERAL PHENOMENA 

were discovered revolving about Jupiter ; and Venus, as 
Copernicus had predicted, was seen exhibiting all the differ- 
ent phases of the Moon, waxing and waning as she does, 
through various forms. Many minute stars, not visible to 
the naked eye, were descried in the Milky- Way ; and the 
largest fixed stars, instead of being magnified, appeared to 
be small brilliant points, an incontrovertible argument in fa- 
vor of their immense distance from us. All his discoveries 
served to confirm the Copernican theory, and to show the 
absurdity of the hypothesis of Ptolemy. 

Although the general arrangement and motions of the 
planetary bodies, together with the figure of their orbits ; 
had been thus determined, the force or power which car- 
ries them around in their orbits, was as yet unknown. 
The discovery of this was reserved for the illustrious New- 
ton.* By reflecting on the nature of gravity — that power 
which causes bodies to descend toward the center of the 
earth — since it does not sensibly diminish at the greatest dis- 
tance from the center of the earth to which we can attain, be- 
ing as powerful on the loftiest mountains as it is in the deep- 
est caverns, he was led to imagine that it might extend to the 
Moon, and that it might be the power which kept her in her 
orbit, and caused her to revolve around the Earth. He was 
next led to suppose that perhaps the same power carried the 
primary planets around the Sun. By a series of calculations, 
he was enabled at length to establish the fact, that the same 
force which determines the fall of an apple to the Earth, 
carries the moons in their orbits around the planets, and the 
planets and comets in their orbits around the Sun. 

To recapitulate briefly: The system (not hypothesis, for 
much of it has been established by mathematical demonstra- 
tion) by which we are now enabled to explain with a beauti- 
ful simplicity the different phenomena of the Sun, planets, 
moons, and comets, is, that the Sun is the central body in 
the system : that the planets and comets move round him in 
elliptical orbits, whose planes are more or less inclined to 
each other, with velocities bearing to each otherf a cer- 
tain ascertained relation, and in times related to their dis- 
tances ; that the moons, or secondaries, revolve in like man- 
ner about their primaries, and at the same time accompany 

* The discovery of Newton was in some measure anticipated by Copernicus, Kepfei 
and Hooke. 

t The orbits or paths of the planets were discovered by tracing the course of th« 
planet by means of the fixed stars. 

What was the discovery of Newton ? How was he led to make it? Recapitulate 
briefly the system by which we are enabled to explain the different celestial pheno- 
mena. 



0*- *&B SOLAR. SYSTEM. 177 

ihem in their motion around the Sun ; all meanwhile revolv- 
ing on axes of their own ; and that these revolutions in 
their orbits, are produced by the mysterious power of at- 
traction. The particular mode in which this system is 
applied to the explanation of the different phenomena, 
will be exhibited as we proceed to consider, one by one, 
the several bodies above mentioned. 

These bodies, thus arranged and thus revolving, consti- 
tute what is termed the solar system. The planets have 
been divided into two classes, primaries and secondaries. 
The latter are also termed moons, and sometimes satel- 
lites. The primaries are those which revolve about the 
Sun, as a center. The secondaries are those which re 
volve about the primaries. There have been discovered 
seventeen primaries; namely, Mercury, Venus, the Earth, 
Mars, Flora, Vesta, Iris, Metis, Hebe, Astrea, Juno, Ceres, 
Pallas, Jupiter, Saturn, Herschel, and Neptune. Mercury 
is the nearest to the Sun, and the others follow in the 
order in which they are named. The nine small planets 
from Flora to Pallas inclusive, were discovered by means 
of the telescope, and, because they are very small, compared 
with the others, are called asteroids. There have been 
discovered nineteen secondaries. Of these, the Earth has 
one, Jupiter four, Saturn seven, Herschel six, and Neptune 
one. All these, except our Moon, as well as the aste- 
roids, are invisible to the naked eye. 

Plate 1, of the Atlas, " exhibits a plan of the Solar System," comprising the re- 
lative magnitudes of the Sun and Planets ; their comparative distances from the 
Sun, and from each other ; the position of their orbits, with respect to each other ; 
the Earth and the Sun ; together with many other particulars which are ex- 
plained on the map. There, the first and most prominent object which claims 
attention, is the representation of the Sun's circumference, with its deep radia- 
tions, bounding the upper margin of the map. It is apparent, however, that this 
segment is hardly one-sixth of the whole circumference of which it is a part. 
Were the map sufficiently large to admit the entire orb of the Sun, even upon so 
diminutive a scale as there represented, we should then see the Sun and Planeis 
in their just proportions — the diameter of the former being 112 times the diame- 
ter of the Earth. 

It was intended, originally, to represent the Earth upon a scale of one inch in 
diameter, and the other bodies in that proportion ; but it was found that it would 
increase the map to four times its size ; and hence it became necessary to assume 
a scale of half &n inch for the Earth's diameter, which makes that of the Sun 56 
inches, and the other bodies, as represented upon the map. 

The relative position of the Planets' orbits is also represented, on a scale as 
large as the sheet would permit. Their relative distances from the Sun as a 
center, and from each other, are there shown correctly. But had we wished to 
enlarge the dimensions of these orbits, so that they would exactly correspond 
with the scale to which we have drawn the planets, the map must have been 
dearly four miles in length. " Hence," says Sir John Herschel, '• the idea that 

What is meant by the Solar System? Into what two classes have the planets been 
divided? Define a primary planet. Define a secondary planet. How many primary 
planets have been discovered ? What are their names, and what the order of their dis- 
tance from the sun? Which of them were discovered by means of the telescope? 
Why are the-fe termed asteroids? How many secondaries have been discovered ? How 
are they distributed among Die primaries? Which oi' the primaries and secondaries 
are invisible to the naked eye J 



178 THE SUX. 

we can convey correct notions on this subject, by drawing circles on paper, is 
out of the question." 

To illustrate this.— Let us suppose ourselves standing on an extended plane, 
or field of ice, and that a globe 4 feet 8 inches in diameter is placed in the center 
of the plane, to represent the Sun. Having cut out of the map the dark circles 
representing the planets, we may proceed to arrange them in their respective 
orbits about the Sun, as follows : 

First, we should take Mercury, about the size of a small currant, and place it 
on the circumference of a circle 194 feet from the Sun ; this circle would repre- 
sent the orbit of Mercury, in the proper ratio of its magnitude. Next, we should 
take Venus, about the size of a rather small cherry, and place it on a circle 302 
feet from the Sun, to represent the orbit of Venus. Then would come the Earth, 
about die sizeof a cherry, revolving in an orbit 500 feet from the Sun. After the 
Earth we should place Mars, about the size of a cranberry, on a circle 762 feet 
from the Sun. Neglecting the Asteroids, some of which would not be larger than 
a pin's head, we should place Jupiter, hardly equal to a moderate-sized melon, 
on a circle at the distance of half a mile (2601 feet) from the Sun ; Saturn, some- 
what less, on a circle nearly a mile (4769 feet) from the Sun ; Herschel, about 
the size of a peach, on the circumference of a circle nearly 2 miles (9591 feet) 
from the Sun ; and last of all Neptune, a little largerthan Herschel, and on a 
circle of nearly 3 miles (15,366 feet) from the Sun. 

To imitate the motions of the planets in the above-mentioned orbits, Mercury 
must describe its own diameter in 41 seconds ; Venus, in 4 minutes 14 seconds ; 
the Earth, in 7 minutes; Mars, in 4 minutes 48 seconds ; Jupiter, in 2 hours 56 
minutes ; Saturn, in 3 hours 13 minutes ; Herschel in 12 hours 16 minutes, and 
Neptune in 23 hours 25 minutes. 

Many other interesting subjects are embraced in Plate 1 ; but they areeithej 
explained on the map, or in the following Chapters, to which they respectively 
relate. 



CHAPTER XIX. 

THE SUN. 

The Sun is a vast globe, in the center of the solar system, 
dispensing light and heat to all the planets, and governing- 
all their motions. It is the great parent of vegetable life, 
giving warmth to the seasons, and color to the landscape. 
Its rays are the cause of various phenomena on the sur- 
face of the earth and in the atmosphere. By their agency, 
all winds are produced, and the waters of the sea are 
made to circulate in vapor through the air, and irrigate 
the land, producing springs and rivers. 

The Sun is by far the largest of the heavenly bodies 
whose dimensions have been definitely ascertained. Its 
diameter is about 887 thousand miles. Consequently, it 
contains a volume of matter equal to fourteen hundred 
thousand globes of the size of the Earth. Of a body so 
vast in its dimensions, the human mind, with all its efforts, 
can form no adequate conception. 

Here let the student refer to Plate 1, where the Relative Magnitudes of the Sun 
and Planets are exhibited. Let him compare the segment of the Sun's cireum 

Mention some of the effects produced by the Sun. What i9 its magnitude compared 
with that of the other heavenly bodies whose dimensions have been estimated 1 What 
is its diameter? How much larger is the Sun than the Earth 7 



THE SUN. 179 

terence, as there represented, with the entire circumference of the Earth. They 
are both drawn upon the same scale. The segment of the Sun's circumference, 
since it is almost a straight line, must be a very small part of what the whole 
circumference would be, were it represented entire. Let the student understand 
this diatrram, and he will be in some measure able to conceive how like a mere 
point the Earth is, compared with the Sun, and to form in his miud some image 
of the vast magnitude of the latter. 

Were the Sun a hollow sphere. perforated with a thousand 
openings to admit the twinkling of the luminous atmosphere 
around it — and were a globe as large as the Earth placed 
at its center, with a satellite as large as our Moon, and at 
the same distance from it as she is from the earth, there 
would be present to the eye of a spectator on the interior 
globe, a universe as splendid as that which now appears to 
the uninstructed eye — a universe as large and extensive as 
the whole creation was conceived to be, in the infancy of 
astronomy. 

The mean distance of the Moon from the Earth is 240.000 
miles, consequently the average diameter of her orbit is 
480,000 miles; and yet, were the Sun to take the place of 
the Earth he would fill the whole orbit of the Moon, and ex- 
tend 200,000 miles beyond it in every direction ! To pass 
from side to side through his center, at rail-road speed 
(30 miles an hour), would require nearly three and a half 
years ; and to traverse his vast circumference nearly eleven 
years. 

The next thing which fills the mind with wonder, is the 
distance at which so great a body must be placed, to occup3% 
apparently, so small a space in the firmament. The Sun's 
mean distance from the Earth, is twelve thousand times the 
Earth's diameter, or a little more than 95 millions of miles. 
We may derive some faint conception of such a distance, 
by considering that the swiftest steamboats, which ply our 
waters at the rate of 200 miles a day, would not traverse it 
in thirteen hundred years ; and, that a cannon ball, flying 
night and day, at the rate of 16 miles a minute, would not 
reach it in eleven years. 

The Sun, when viewed through a telescope, presents the 
appearance of an enormous globe of fire, frequently in a 
state of violent agitation or ebullition ; dark spots of irregu- 
lar form, rarely visible to the naked eye, frequently pass 
over his disc, from east to west, in the period of nearly four- 
teen days. 

These spots are usually surrounded by a penumbra, or 



What is the whole distance between the Earth and the Moon, compared with the 
diameter of the Sun ! Give some illustration t-> en ible u> to conceive ol the magnitude 
of the Sue. Whit is the nisi m<-.- nf the .Sir.) f onn the Earth? Give some illustration 
to enable us to con vt'hat is \\\^ aiea-aran-e ot" (he Sun when 

viewed thi'oiiu'h a teics -r[v ? i.i . ; i:-,m d<> tin spot-; seen on the Sun pan two* 
the disc? In what direction do t be ;h. 1. ap, eaauce. 



180 THE SUN. 

less deeply shaded border, and that, by a margin of light, 
more brilliant than that of the Sun. A spot, when first seen 
on the eastern edge of the Sun. appears like a line which 
progressively extends in breadth, and increases its apparent 
velocity, till it reaches the middle, when it begins to con- 
tract, and to move less rapidly, till it ultimately disappears, 
at the western edge. In some rare instances, the same spots 
re-appear on the east side, and are permanent for two or 
three revolutions. But, as a general thing, the spots on the 
Sun are neither permanent nor uniform. Sometimes seve- 
ral small ones unite into a large one ; and, again, a large 
one separates into numerous small ones. Some continue 
several days, weeks, and even months, together; while 
others appear and disappear, in the course of a few hours. 
Those spots that are formed gradually, are, for the most 
part, as gradually dissolved ; whilst those that are suddenly 
formed, generally vanish as quickly. 

It is the general opinion, that spots on the Sun were first 
discovered by Galileo, in the beginning of the year 1611; 
though Scheiner, Harriot, and Fabricius, observed them 
about the same time. During a period of 18 years from this 
time, the Sun was never found entirely clear of spots, ex- 
cepting a few days in December, 1624: at other times, there 
were frequently seen twenty or thirty at a time, and in 
1625, upwards of fifty were seen at once. From 1650 to 
1670, scarcely any ppots were to be seen ; and, from 1676 
to 1684, the orb of the Sun presented an unspotted disc. 
Since the beginning of the eighteenth century, scarcely a 
year has passed, in which ipots have not been visible, and 
frequently in great numbers. In 1799, Dr. Herschel ob- 
served one nearly 30.000 miles in breadth. 

A single secoid of angular measure, on the Sun's disc, a^seen from the Eartli, 
corresponds to 462 miles; and a circle of this diameter (containing therefore 
neady 220,000 .-quafe miles) is the least space which ran be dsfncfly discerned on 
the Sun as a visible urea, even by the most powerful ',da>ses. Spots \\n\f been 
observed, however, whose linear diameter has been more than 44,000 miles; 
and. if some records are to be trusted, of even still greater ex ent. 

Dr. Dick, in a letter to the author, says: "I have for many years examined 
the solar spots wiih considerable minuteness, and have federal times seen .-potg 
which were nor less than the one twenty-fifth pait of die Sun's diame er, which 
would make them about 22,192 miles in diameter, yet they wee visible neither 
to the naked eye. nor through au opera trlass. murriifjr'm? about three tunea. 
And, iheretorc, if any bpots have been visible to the nake«l eye — which we must 
believe, unless we refuse respectable testimony — they could not have beeu much 
less than 50,000 mdes in diameter." 

The apparent direction of these spots over the Sun's 
disc, is continually varying. Sometimes they seem to move 

Do the same spot3 ever re-appear on the east side ? Are the spots generally perma- 
nent and uniform * Describe their irregularities. Who i.< it «reneraJry supposed first 
diseoverea spots on the Sun .' Who else observed them about the same time 7 What 
was the breadth of the one seen by Dr. Herschel in lTSJ.i In what direction do Lh* 
spots on the Sun sppeor to move? 



THE SUN. 181 

across it in straight lines, at others in curve lines. Some- 
times the spots seem to move upward, as they cross from 
cast to west, while at other times they incline doicnward. 
while the curve lines are sometimes convex towards one 
pole of the Sun, and sometimes towards the other. All 
these phenomena are owing to the fact that the axis of the 
Sun is inclined to the Ecliptic, so that viewing him from dif- 
ferent points in the Earth's orbit, the apparent direction of 
the spots must necessarily vary. The following diagrams 
may serve to illustrate : 

Fig. 1. N Fig. 2. Fig. 3. Fig. 4. 




S December. March. June. September. 

These figures are representations of the body of the Sun. 
The dotted horizontal line running through his center, is the 
plane of the Ecliptic. The lines N S, &c. represent the 
axis of the Sun. and his North and South poles. In 
November and December we have, so to speak, a side view 
of f he axis of the Sun, his poles being equi-distant from us. 
At this time the spots, entering upon his left or eastern limb, 
incline downward, and pass over his disc in a direct line as 
at Fig. 1. Three months from this time, the Earth having 
advanced ninety degrees in her orbit, and the axis of the 
Sun remaining fixed, his North pole will be inclined towards 
us, and the spots will seem to pass over his surface in curve, 
lines, as shown in Fig. 2. On the first of June the Earth is 
directly opposite the point from which we view the Sun in 
December, and his poles are again equi-distant from us. 
At this time the spots again revolve in straight lines, and 
seem to move upward over the Sun's disc as rhown at Fig. 
3. In September the South pole of the Sun is inclined to- 
wards the Earth, and the spots describe curve line~ convex 
towards the North pole, as shown at Fig. 4. 

The cut exhibits the penumbra, surrounding the more 
deeply shaded portion in the center of the spots, and illus- 
trates the cause and progress of their apparent expansion »s 
they approach the Sun's center, and their contraction «> 
they recede from it. 

The annexed cut. which can be understood without further 



What causes the variations in their direction ? How c'o tha spots appear to move in 
December? March? Jurift? September? Why do the spots appear larger as Utfjr 
approucA the Sun'e center ? Do thu spots revolve with regularity, or utrterwUe ? 



182 THE SUN. 

explanation, will serve to make this still more clear to the 
mind of the student. 



March. 

From the regularity with which these spots revolve, it is 
concluded with good reason, that they adhere to the sur- 
face of the Sun and revolve with it. They are all found 
within 30° of his equator, or within a zone 60 in width. 

The apparent revolution of a spot, from any particular 
point of the Sun's disc, to the same point again, is accom- 
plished in 27 days, 7 hours, 26 minutes, and 24 seconds ; but 
during that time, the spot has, in fact, gone through one re- 
volution, together with an arc, equal to that described by the 
Sun, in his orbit, in the same time, which reduces the time 
of the Sun's actual rotation on his axis, to 25 days, 9 hours, 
and 36 minutes. 

The part of the Sun's disc not occupied by spots, is far 
from being uniformly bright. Its ground is finely mottled 
with an appearance of minute, dark dots, or pores, which, 
attentively watched for several days in succession, are found 
to be in a constant state of change.* 

What the physical organization of the Sun may be, is a 
question which astronomy, in its present state, cannot solve. 
It seems, however, to be surrounded by an ocean of inex- 
haustible flame, with dark spots of enormous size, now and 
then floating upon its surface. From these phenomena, Sir 
W. Herschel supposed the Sun to be a solid, dark body, 
surrounded by a vast atmosphere, almost always filled with 
luminous clouds, occasionally opening and disclosing the 
dark mass within. The speculations of Laplace were dif- 

* See Journal of Observations on a Cluster of Spots upon the Sun's Disc, in the 
month of March, 1837. By E. P. Mason. 

What conclusions have been drawn frnm these phenomena? What is the apparent 
time occupied by a spot in revolving from any particular point of the Sun's disc to the 
same point again 1 What is the actual time occupied by the revolution of the spot, 
^ind of course by the Sun on its axis ' Have we been able to determine what the phy 
sical organization of the Sun is ? What was the theory of Sir W. Herschel in retard to 
this subject ? 



MERC DRV. 183 

ferent He imagined the solar orb to be a mass of fire, and 
the violent effervescences and explosions seen on its surface. 
to be occasioned by the eruption of elastic fluids, formed in 
its interior, and the spots to be enormous caverns, like the 
craters of our volcanoes. Others have conjectured that 
these spots are the tops of solar mountains, which are some- 
times left uncovered by the luminous fluid in which they arc 
immersed. 

Among all the conflicting theories that have been ad- 
vanced, respecting the physical constitution of the Sun. 
there is none entirely free from objection. The prevailing 
one seems to be, that the lucid matter of the Sun is neither 
a liquid substance, nor an elastic fluid, but that it consists of 
luminous clouds, floating in the Sun's atmosphere, which 
extends to a great distance, and that these dark spots are the 
opaque body of the Sun, seen through the openings in his 
atmosphere. Herschel supposes that the density of the 
luminous clouds need not be greater than that of our 
Aurora Borealis, to produce the effects with which we are 
acquainted. 

The similarity of the Sun, to the other globes of the sys- 
tem, in its supposed solidity, atmosphere, surface diversified 
with mountains and valleys, and rotation upon its axis, ha3 
led to the conjecture that it is inhabited, like the planets, 
by beings whose organs are adapted to their peculiar cir- 
cumstances. Such was the opinion of the late Dr. Herschel. 
who observed it unremittingly, with the most powerful tele- 
scopes, for a period of fifteen years. Such, too, was the 
opinion of Dr. Elliot, who attributes to it the most delightful 
scenery ; and, as the light of the Sun is eternal, so, he 
imagined, were its seasons. Hence he infers that this lumi- 
nary offers one of the most blissful habitations for intelli- 
gent beings of which we can conceive. 



MERCURY. 



Mercury is the nearest planet to the Sun that has vet 
been discovered; and with the exception of the asteroids, 
is the smallest. Its diameter is only 3,140 miles. Its bulk- 
therefore is about 16 times less than that of the Earth. It 

What was that of Laplace ? What is the prevailing theory ? What circumstances 
have led to the conjecture that the Sun is inhabited? What was the opinion of Dr. 
Herschel on this point/ How Ion? had he observed it unremittingly, and with the 
most powerful telescopes ? What was the opinion of Dr. Elliot upon the same point 1 

What is tin' distance of Mercury from the Sun? What is its magnitude compared 
with that of the other planets? What is its diameter? 



184 MF.RCUltY. 

would require more than 20 millions of such globes to com- 
pose a body equal to the Sun. 

Here the student should refer to the diagrams, exhibiting the relative magni- 
ludes and distances of the Sun and Planots, P.ate I. And whenever this subject 
recurs in the course of this work, the student should recur to the figures of this 
plate, until he is able to form in his mind distinct conceptions of the relative 
magnitudes and distances of all the Planets. The Sun and Planets being spheres 
i.;- nearly so, their relative bulks are estimated -by comparing the cubes of their 
dameters : thus, the diameter of Mercury being 3140 miles, and that of the Earth 
W12 ; their bulks are as the cube of 3110, to the cube of 7912, or as 1 to 1G, nearly. 

It revolve^ on its axis from west to east in 24 hours, 5 min- 
utes, and 28 seconds ; which makes its day about 10 minutes 
longer than ours. It performs its revolution about the Sun 
in a few minutes less than 88 days, and ai a mean distance 
of nearly 37 millions of miles. The length of Mercury's 
year, therefore, is equal to about three of our months. 

The rotation of a planet on its axis, constitutes its day ; its revolution about the 
Sun constitutes its year. 

Mercury is not only the most dense of all the planets, but 
receives from the Sun s-x and a half times as much light and 
heat as the Earth. The truth of this estimate, of course, 
depends upon the supposition that the intensity of solar light 
and heat at the planets, varies inversely as the squares of 
their distances from the Sun. 

This law of analogy, did it exist with rigorous identity at 
all the planets, would be no argument against their being 
inhabited ; because we are bound to presume that the All- 
wise Creator has attempered every dwelling-place in his 
empire to the physical constitution of the beings which he 
'•as placed in it. 

From a variety of facts which have been observed in relation to the produc- 
tion of caloric, it does not appear probable, 'hat the degree of heat on the surface 
of the different planets depends on their respective distances from the Sun. It 
is more probable, that it depends chieliy on the distribution of the substance of 
t-aloric on the surfaces, and throughout the atmospheres of these bodies, in dif- 
ferent quantities, according to the different situations which they occupy iu the 
solar system ; and that these different quantities of caloric are put into action by 
(he influence of the solar rays, so as to produce that decree of sensible heat 
requisite to the wants, and to the greatest benefit of each of the planets. On this 
hypothesis, which is corroborated by a great variety of facts and experiments, 
i\ere may be no more sensible heat experienced on the planet Mercury, than ou 
die surface of Herschel, which is fifty times farther removed from the Sun. 

How many such bodies would it require to compose a body equal to the Sun ? Hoto 
vre the relative bulks of the planets estimated I In what direction does it revolve ou 
rts axis, a d what time does it occupy in the revolution 1 In how long time does it 
perform its revolution about the Sun' What is its mean distance from the Sun? 
Whai, then, is the length otits year compared with ours > What measures a plana'* 
lUiy ? What measures its year ? What is the density of Mercury, compared with that 
af the other planets 1 How much light and heat does it receive compared with th« 
earth 1 ? On what supposition does the truth of this estimate depend? If this were 
really the fact in regard to the planets, would it be any argument against their being 
inhabited 1 On xohat does the decree of heat at the different planets probably depend! 
Why have astronomers been able to make but comparatively few discoveries respect- 
in* Mercury ? 



MERCURY. 185 

Owing to the dazzling brightness of Mercury, the swiftness 
of its motion, and its nearness to the Sun, astronomers have 
made but comparatively few discoveries respecting it. When 
viewed through a telescope of considerable magnifying power, 
it exhibits at different periods, all the various phases of the 
Moon; except that it never appears quite full, because its 
enlightened hemisphere is never turned directly towards the 
Earth, only when it is behind the Sun, or so near to it. as 
to be hidden by the splendor of its beams. Its enlightened 
hemisphere being thus always turned towards the Sun, and 
the opposite one being always dark, prove that it is an 
opaque body, similar to the Earth, shining only in the light 
which it receives from the Sun. 

The rotation of Mercury on its axis, was determined from 
the daily position of its horns, by M. Schroeter, who not on!y 
discovered spots upon its surface, but several mountains in 
its southern hemisphere, one of which was lOf miles high— 
nearly three times as high as Chimborazo, in South America. 

It is worthy of observation, that the highest mountains which have been discov 
ered in Mercury, Venus, the Moon, and perhaps we may add the Earth, are ai! 
situated in their southern hemispheres. 

During a few days in March and April, August and Sep- 
tember, Mercury m^r be seen for several minutes, in the 
morning or evening twilight, when its greatest elongatious 
happen in those months; in all other parts of its orbit, it is 
too near the Sun to be seen by the naked eye. The greatest 
distance that it ever departs from the Sun, on either sk.c. 
varies from 16° 12', to 2S° 4S', alternately. 

The distance of a planet from the Sun, as seen from the Earth, (measured in 
degrees,) is called its elongation. The greatest absolute distance of a planet from 
the Sun is denominated its aphelion, and the least its perihelion. On the diagram 
exhibiting tlie Relative Position of the Planets' Orbits, [Plate i,] these points are 
represented by little dots in the orbits at the extremities of the right lines whicn 
meet them ; the Perihelion points being above the Ecliptic, the Aphelion poinrs 
below it. 

The revolution of Mercury about the Sun. like that of all 
the planets, is performed from west to east, in an orbit which 
is nearly circular. Its apparent motion as seen from the 
earth, is, alternately, from west to east, and from east to west. 
nearly in straight lines; sometimes, directly across the face 



What is its appearance when viewed through a telescope of considerable magnify 
tng rower? What circumstances prove that it is an opaque body, shining only with 
the light of the Sun? How was the rotation of Mercury on its avis determined, anu 
by whom? What did he discover on its surface? What was the altitude of the 
lushest mountain which he saw? In which hemisphere are the highest ?ncrunta:ns 
Which, have been discovered in Mercury, Venus, and the Moon, situated. Dots the 
ct exist in regard to the Earth] During what months may Mercury he src:i 
for a few days, and in what parts of the day ? Why is it visible at these time.<. an i 
not at others? What are the greatest distances which it departs from thi 
either side? What is the Elongation of a planet? What is its Aphelion 1 
its Perihelion •' In what direction does Mercury revolve about the Sun? What is '•: 
figure of its orbit? Describe its apparent motion, as seen from the Earth. 



186 MERCURY. 

of the Sun, but at all other times, either a little above, or a 
little below it. 

Being commonly immersed in the Sun's rays in the even- 
ing, and thus continuing invisible till it emerges from them 
in the morning, it appeared to the ancients like two distinct 
ntars. A long series of observations was requisite, before 
they recognized the identity of the star which was seen to 
recede from the Sun in the morning with that which ap- 
proached it in the evening. But as the one was never seen 
until the other disappeared, both were at last found to be the 
same planet, which thus oscillated on each side of the Sun. 

Mercury's oscillation from west to east, or from east to 
west, is really accomplished in just half the time of its revo- 
lution, which is about 44 days; but as the Earth, in the mean 
lime, follows the Sun in the same direction, the apparent 
elongations will be prolonged to between 55 and 65 days. 

The passage of Mercury directly between the Earth and 
the Sun, and apparently over his disc, is called a Transit. 
This would occur at every revolution, if his orbit lay in the 
name plane with that of the Earth ; but as it does not. but >3 
inclined to the Earth's orbit. 7° 9'. and consequently cuts 
it at two opposite points in the Ecliptic; and as transits 
can occur only when Mercury is in the plane of the Earth's 
orbit, it follows that they can take place only occasionally; 
and when he is passing these two opposite points of his orbit. 
The following diagram will illustrate our meaning: 

THE ECLIPTIC, NODES, TRANSITS. &C. 



J Aug. 



\ 



X 



r ;p horizontal circle represents the orbit of the Earth, in which she is seen at 
KHir different points. Within this circle is seen the orbit of Mercury, cutting or 
l>a»iii<r through the plane of the former at two opposite points called the Nodes. 
A N and D N mark the ascending and descending Nodes, as also the char- 
How did it appear to the ancients? What was the cause of this appearance 7 How 
"•e e these apparently two distinct stars at last found to be but one? What is the 
U'tM'l period of each elongation of Mercury J What the apparent period? What is 
the cmise of thig difference ? What does the expression, transit of Mercury, signify J 
^ hy does it not make a transit at every revolution? 



MERCURY. 187 

aeters £ and ^. LN. designates the line of the Nodes. Now it is obvious that if 
Mercury should he at his %£ -when the Earth is in H, and exactly on the line of 
the Nodes, as shown in the cut. the former would appear to pass Tike a dark spot, 
upicard over the Sun's disc. On the other hand, should the two planeis meet on 
the line of the Nodes at 9?, Mercury would appear to pass downward over the 
face of the Sun. 

Again ; as these Node points are on opposite sides of the Ecliptic, and are pass- 
ed by the Earth in May and November, it follows that all transits of Mercury 
must occur in one or the other of these months. They are, therefore called the 
Node months. 1 s is shown in the diagram, the Earth passes the ascending 
Node of Mercury in November, and the descending in May ; the former of which 
is in the- 16th degree of Taurus, and the latter in the 16th degree of Scorpio. 

For the relative position of the planets' orbits, and their inclination to the plane 
of the Ecliptic, see Plate 1, of the Atlas. Here the dotted lines continued from 
the dark lines denote the inclination of the orbits to the plane of the Ecliptic, 
which inclination is marked in figures on them. Let the student fancy as many 
circular pieces of paper intersecting each other at the several angles of inclination 
marked on the Plate, and he will be enabled to understand more easily what is 
meant by the inclination of the planets' orbits. 

The following is a list of all the Transits of Mercury from the time the first was 
observed by Gassendi, November 6. 1631, to the end of the present century. 
J 031 Nov. 6. 1707 May 5. I 1776 Nov. 2. 1835 Nov. 7. 

1644 Nov. 6. 1710 Nov. 6. 1732 Nov. 12. 1.345 May 8. 

1651 Nov. 2. 1723 Nov. 9. | 17S6 May 3. 1343 Nov. 9. 

1661 Ma v 3. 1736 Nov. 10. I . 1739 Nov. 5. 1861 Nov. 11. 

1064 Not. 4. 1740 Nov. 2. 1799 May 7. 1863 Nov. 4. 

1674 Mav 6. 1743 Nov. 4. | 1802 Nov. 8. 1373 May 6. 

1677 Nov. 7. 1753 Mav 5. I 1815 Nov. 11. 1331 Nov. 7. 

1690 Nov. 9. 1756 Nov. 6. 1822 Nov. 4. 1591 May 9. 

1697 Nov. 2. 1769 Not. 9. | 1832 May 5. 1894 Nov. 10. 

B" comparing the mean motion of any of the planers with the mean motion of 
the Earth, we may, in like manner, determine the periods in which these bodies 
will return to the' same points of their orbit, and the same positions with respect 
to the Sun. The knowledge of these periods will enable us to determine the 
hour when the planets rise, set and pass the meridian, and in general, all the 
phenomena dependent upon the relative position of the Earth, theplanet and the 
Sun : for at the end of one of these periods they commence again, and all recur 
in the same order. We have only to find a number of sidereal years, in which the 
planet completes exactly, or very nearly, a certain number of revolutions ; that 
is, to find such a number of planetary revolutions, as, when taken together, shall 
be exactly equal to one. or auy number of revolutions of the Earth. " In the case 
of Mercury, this ratio will be as 87.969 is to 365.256. Whence we find that, 

7 periodical revolutions of the Earth, are equal to 29 of Mercury : 

13 periodical revolutions of the Earth, are equal to 54 cf Mercury: 

33 periodical revolutions of the Earth, are equal to 137 of Mercury : 

46 periodical revolutions of the Earth, are equal to 191 of Mercury. 
Therefore, transits of Mercury, at the same node, may happen at intervals of 7, 
13.3-^, 46. «tc. years. Transits of Venus, as well as eclipses of the Sun and Moon, 
are calcnlatedupon the same principle. 

The sidereal revolution of a planet respects its absolute motion ; and is meas- 
ured by the time the planet takes to revolve from any fixed star to the same star 
again. 

The synodical revolution of a planet respects its relative motion ; and is meas- 
ured by the time that a planet occupies in coming back to the same position with 
respect to the Earth and the Sun. 

What are the roints where the orbits of the planets intersect the orbit of the Rarth 
called? Where is Mercury's ascending node? Where is its descending node? Ib 
v hat months must the transit of Mercury occur for many ages to come ? Why must 
they occur in these months •' Hcno can xce determine the periods in which the plantu 
will reiurn to the same points of their orbits, and the sarne positions in retpect to the 
Svn ? Why is it useful to knene these periods] State the method nfmakinz the com- 
puterion. What will the ratio be in th* case of Mercury ? State the ratio between 
the periodical revolutions of the. Earth and Mercury At what intervals, then, may 
tra/isits of Mercury at the same nod* happen 1 Upon what principle are transit! of 
V*nus and eciips's of the Sun and Moon calculated? What is the sidereal revolution 
Ufa planet/ What is the synodical revolution? What is the time of the sidereal 
retoution of Mercury 1 Sta:e the metiiod of computing the time of the synodical 
revolution. Compute 'the synodical revolution of Mercury. 



15 



The sidereal revolution of Mercury, is 87d. 23h. 15m. 44s. Its s>/nodical revo- 
lution is found by dividing the whole circumference of 360° by its relative motion 
in respect to the Earth. Thus, the mean daily motion of Mercury is 14732". 555; 
that of the Earth is 3548" .318 ; and their difference is 11134" .237, being Mer- 
cury's relative motion, or what it gains on the Earth every day. Now bv simple 
proportion, 11184" .237 is to 1 day, as 360° is to 115d. 21h. 3', 24", the period of a 
synodical revolution of Mercury. 

The absolute motion of Mercury in its orbit, is 109,757 
miles an hour; that of the Earth, is 68,288 miles: the dif- 
ference, 41,469 miles, is the mean relative motion of Mercury, 
with respect to the Earth. 



VENUS. 



There are but few persons who have not observed a beau- 
tiful star in the west, a little after sunset, called the evening 
star. This star is Venus. It is the second planet from the 
Sun. It is the brightest star in the firmament, and on this 
account easily distinguished from the other planets. 

If we observe this planet for several days, we shall find 
that it does not remain constantly at the same distance from 
the Sun, but that it appears to approach, or recede from him, 
at the rate of about three-fifths of a degree every day; and 
that it is sometimes on the east side of him, and sometimes 
on the west, thus continually oscillating backwards and for- 
wards between certain limits. 

As Venus never departs quite 48° from tne Sun, it is never 
seen at midnight, nor in opposition to that luminary; being 
visible only about three hours after sunset, and as long before 
sunrise, according as its right ascension is greater or less 
than that of the Sun. At first, we behold it only a few mi- 
nutes after sunset; the next evening we hardly discover any 
sensible change in its position ; but after a few days, we per- 
ceive that it has fallen considerably behind the Sun, and 
that it continues to depart farther and farther from him, set- 
ting later and later every evening, until the distance between 
it and the Sun, is equal to a little more than half the space 
from the horizon to the zenith, or about 46°. 

It now begins to return towards the Sun, making the same 
daily progress that it did in separating from him, and to set 
earlier and earlier every succeeding evening, until it finally 
sets with the Sun, and is lost in the splendor of his light. 

What is the rate per hour of the absolute motion of Mercury in its orbit? Of the 
Earth? What is the mean relative motion of Mercury with respect lo the Earth? 
What beautiful star sometimes appears in the west a little after sunset ? What is the 
comparative distance of Venus from the Sun? What is its comparative brightness? 
In what direction is its apparent motion? Why is it never seen at midnight, nor in 
opposition to the Sun? At what times is it visible? How long after sunset is it 
when we first behold it in the west? Describe its changes of position. 



VENUS. 1 89 

A few days after the phenomena we have now described, 
we perceive, in the morning, near the eastern horizon, a 
bright star which was not visible before. This also is Venus, 
which is now called the morning star. It departs farther 
and farther from the Sun, rising a little earlier every day. 
until it is seen about 46° west of him, where it appears sta- 
tionary for a few days; then it resumes its course towards 
the Sun, appearing later and later every morning, until it 
rises with the Sun, and we cease to behold it. In a lew days, 
the evening star again appears in the west, very near the 
setting-sun, and the same phenomena are again exhibited. 
Such are the visible appearances of Venus. 

Venus revolves about the Sun from west lo east in 224= 
days, at the distance of about 68 millions of miles, moving 
in her orbit at the rate of 80 thousand milei ai hour. She 
turns around on her axis orice in 23 hours, 21 minutes, and 
7 seconds. Thus her day is about 25 minutes shorter than 
ours, while her year is equal to 7| of our months, or 32 weeks. 

The mean distance of the Earth from the Sun is estimated 
at 95 millions of miles, and that of Venus being 6S millions, 
the diameter of the Sun, as seen from Venus, will be to his 
diameter as seen from the Earth, as 95 to 68, and the surface 
of his disc as the square of 95 to the square of 68, that is, as 
9025 to 4626, or as 2 to 1 nearly. The intensity of light and 
heat being inversely as the squares of their distances from 
the Sun, Venus receives twice as much light and heat as 
the Earth. 

Her orbit is within the orbit of the Earth; for if it were 
not, she would be seen as often in opposition to the Sun, as 
in conjunction with him ; but she was never seen rising in 
the east while the Sun was setting in the west. Nor was 
she ever seen in quadrature, or on the meridian, when the 
Sun was either rising or setting. Mercury being about 23° 
from the Sun, and Venus 46°, the orbit of Venus must be 
outside of the orbit of Mercury. 

The true diameter of Venus is 7700 miles; but her ap- 
parent diameter and brightness are constantly varying, ac- 
cording to her distance from the Earth. When Venus and 
the Earth are on the same side of the Sun, her distance 
from the Earth is only 26 millions of miles; when they are 

In what direction, and in what time does Venus revolve about the Sun? "What is 
her distance liom the Sun .' What is the rate per hour of her motion in her orlut ? In 
what time does she revolve on her axis ? How are the lengths of her day and year, 
compared with those of the Earth? Hov much larger does the Sun appear at Venus 
than he does at the Earth ? How much more liirht and heat does she receive from 
him than the Earth ? How much farthei is Venus from the Sun than Mercury ? On 
which side of the orbit of Mercuiy must her orbit be ? What i.; her true diameter? 
In what proportion do her apparent diameter and brightness constantly vary > What 
u her distance from the Earth when they are both on the same side of the Sun/ 



190 VENUS. 

on opposite sides of the Sun, her distance is 164 millions of 
miles. Were the whole of her enlightened hemisphere 
turned towards us, when she is nearest, she would exhibit a 
light and brilliancy twenty-five times greater than she gene- 
rally does, and appear like a small brilliant moon ; but, at 
that time, her dark hemisphere is turned towards the Earth. 

When Venus approaches nearest to the Earth, her apparent, or observed diam- 
eter, is 61"2 ; when most remote, it is only 9" .6 : now 61" .2-=-9".6=6|, hence 
when nearest the Earth her apparent diameter is 6? times greater than when most 
distant, and surface of her disc (61)^, or nearly 41 times greater. In this work, 
the apparent size of the heavenly bodies is estimated from the apparent surface of 
their discs,which is always propor tional to the squares of their apparent diameters, 

When Venus' right ascension is less than that of the Sun, 
she rises before him ; when greater, she appears after his 
setting. She continues alternately morning and evening 
star, for a period of 292 days, each time. 

To those who are but little acquainted with astronomy, it 
will seem strange, at first, that Venus should apparently con- 
tinue longer on the east or west side of the Sun, than the 
whole time of her periodical revolution around him. But it 
will be easily understood, when it is considered, that while 
Venus moves around the Sun, at the rate of about 1° 36' of 
angular motion per day, the Earth follows at the rate of 59'; 
so that Venus actually gains on the Earth, only 37' in a day. 

Now it is evident that both planets will appear to keep on 
the same side of the Sun, until Venus has gained half her 
orbit, or 180° in advance of the Earth; and this, at a mean 
rate, will require 292 days, since 292x37 / =10804 / , or 180° 
nearly. 

Mercury and Venus are called Interior planets, because 
their orbits are within the Earth's orbit, or between it and 
the Sun. The other planets are denominated Exterior, 
because their orbits are without or beyond the orbit of the 
Earth. \Plate I.~\ As the orbits of Mercury and Venus 
lie within the Earth's orbit, it is plain, that once in every 
synodical revolution, each of these planets will be in con- 
junction on the same side of the Sun. In the former case, 
the planet is said to be in its inferior conjunction, and in the 
latter case, in its superior conjunction ; as in the following 
figure. 

What is it when they are on opposite sides of the Sun 1 Which hemisphere is turned 
towards the Earth when she is nearest to us 1 Were her enlightened hemisphere turned 
towards us at that time, how would her light and brilliancy be compared with that 
which she generally exhibits, and what would be her appearance 7 What is the length 
qf her apparent diameter when she is nearest to the Earth ? What is it ichen she is 
most remote? How is the apparent size of a heavenly body estimated in this work? 
In what circumstances does Venus rise before, and in what set after, the Sun ? How 
long does she continue, each time, alternately morning and evening star? Why does 
she appear longer on the east or west side of the Sun than the whole time of her peri- 
odical revolution around him? Why are Mercury and Venus called Interior planets! 
Why are the other planets termed Exterior planets? 



191 



CONJUNCTION AND OPPOSITION OF THE PLANET3. 




Earth y 

Mars in^g Opposition, 

The period of Venus' synodical revolution is found in the same manner aa 
that of Mercury ; namely, by dividing the whole circumference of her orbit by 
her mean relative motion in a dav. Thus, Venus' absolute mean daily motion 
is 1°36'7".S. the Earth's is 59' 3". 3. and their difference is 36' 59".5. Divide 
860° by 36' 5S".5, and it gives 533.920, or nearly 534 days for Venus' synodical 
revolution, or the period in which she is twice in conjunction with the Earth. 

Venus passes from her inferior to her superior conjunction 
in about 292 days. At her inferior conjunction, she is 26 
millions of miles from the Earth; at her superior conjunc- 
tion, 164 millions of miles. 

It might be expected that her brilliancy would be propor- 
tionally increased, in the one case, and diminished, in the 
other ; and so it would be. were it not that her enlightened 
hemisphere is turned more and more from us, as she ap- 
proaches the Earth, and comes more and more into view as 
she recedes from it. It is to this cause alone that we must 
attribute the uniformity of her splendor as it usually appears 
to the naked eye. 

How often in every synodical revolution, will each of these planets be in conjunction 
on '.he surae side of the Sun that the Earth is? How often on the opposite side? 
Explain this. What names distinguish these two species of conjunction 1 lino it 
the synodical revolution of Venus foitmi) Make the calculation. How lonff is she 
-' from her inferior to her suDerior conjunction ? How far is she from the 
Earth at her interior conjunction How far at her superior? Why is not her bril- 
liancy proportionally increased in the former case, and diminished in the latter 1 What 
appearances do Mercury and Venus present to u» at different times ? 



192 VENUS. 

Mercury and Venus present to us, successively, the various 
shapes and appearances of the Moon ; waxing and waning 
through different phases, as shown in the following cut, from 
the beautiful crescent to the full rounded orb. This fact 
shows, that they revolve around the Sun, and between the 
Sun and the Earth. 



PHASES 


OF VENDS AS 


SHE REVOLVES 


AROUND 


THE SUN 








O 


HO 


H 






Iffl 




hj^32 


^iSfflH 


K|: 


BE 


El 




O 


Sifi 



Let the pupil endeavor to explain these phases on any 
other supposition, and he will be convinced that the system 
of Ptolemy is erroneous, while that of Copernicus is con- 
firmed. 

It should be remarked, however, that Venus Is never seen when she is entirely 
full, except once or twice in a century, when she passes directly over the Sun's 
disc. At every other conjunction, she is either behind the Sun. or so near him 
as to'be hidden by the splendor of his light.* The preceding diagram better il- 
lustrates the various appearances of Venus, as she moves around the Sun, than 
any description of them could do. 

From her inferior to her superior conjunction, Venus ap- 
pears on the west side of the Sun, and is then our morning 
star; from her superior to her inferior conjunction she ap- 
pears on the east side of the Sun, and is then our evening 
star. 

These phenomena are illustrated by the diagram on the 
following page. 



* The eminent astronomer. Thomas Dick, LL. D., well known in this country as the 
• Jthorof the Christian Philosopher, Philosophy of a Future State, Arc, in a review 
uf this remark, observes, " This ought not to be laid down as a general truth. About 
the year 1313. I made a great variety of observations on Venus in the day-time, by an 
equatorial instrument, and found that she could be seen when only 1° 27' from the Sun's 
margin, and consequently may be seen at the moment of her superior conjunctiou, 
when her geocentric latitude, at that tim«. equals or exceeds 1° 43'. I have some faint 
expectations of being able to see Venus in the course of two or three days, at her supe- 
rior conjunction, if the weather be favorable."— March 3, IS34. 



) of these phases ? Whn*t system 



"Wh.it supposition is necessary for the explanatio .. 
do they tend to refute.' What system do they confirm? How often is Venus seen 
when she is entirely full 7 Why is she not seen at the full oftener) In what part of 
her orbit does Venus appear on the west side of the Sun » In what on the ea*t> ' 
w'—' parts is she alternately morning and evening »tar» 



193 



VENUS A3 MORNING AND EVENING STAR. 
.'East. jsa. West.v 




Let the plane A B represent the sensible or visible horizon, C D the appa- 
rent daily path of the Sun through the heavens, and E the Earth in her apparent 
position. The Sun is seen at three points, namely, rising in the east, on the meridi- 
an, and setting in the west. Venus also is shown ai each of these points, revolving 
around him from west to east, or in the direction of the arrows. Now it is obvi- 
ous that when she is at F, or west of the Sun. she rises before the Sun as at 
G, and sets before him as at H. She is then morning star. On the other hand, 
when she is east of the Sun as at I, she rises after him as at J, and lingers after 
him when he sets, as at K. She is then evening star. 

From this diagram the learner will also understand why 
it is that Venus can be seen with a telescope in the day- 
time, whether she be morning or evening star ; and also why 
she appears to oscillate, first one side of the Sun and then 
the other. Were the diurnal motion of the Earth suspended 
so that the Sun could remain fixed upon the meridian, we 
could see Venus perform her entire journey around the Sun. 

Like Mercury, she sometimes seems to be stationary. Her 
apparent motion, like his, is sometimes rapid ; at one time, 
direct, and at another, retrograde ; vibrating alternately 
backwards and forwards, from west to east, and from east 
to west. These vibrations appear to extend from 45° to 47°> 
on each side of the Sun. 

Consequently she never appears in the eastern horizon, more than three houra 
before sunrise, nor continues longer in the western horizon, after sunset. Anj 
star or planet, therefore, however brilliant it may appear, which is seen earlier 
or later than this cannot be Venus. 

In passing from her western to her eastern elongation, her 
motion is from west to east, in the order of the signs ; it is 
thence called direct motion. In passing from her eastern to 
her western elongation, her motion with respect to the Earth, 
is from east to west, contrary to the order of the signs ; it i<s 
thence denominated retrograde motion. Her motion appears 



Describe her apparent motion. Hu\v far on each side of the Sun do the vibrations 
of Venus extend ? What is the direction of her motion while she passes from ht r west- 
ern to her eastern elongation ? Why is it called direct motion? What is its direction 
us «he passes from her eastern to her western elongation! Why u it called rutiograde 

17 



194 VENUS. 

quickest about the time of her conjunctions ; and she seems 
stationary at her elongations. She is brightest about 36 
days before and after her inferior conjunction, when her 
light is so great as to project a visible shadow in the night, 
and sometimes she may be seen, with the naked eye even at 
noon-day. 

DIRECT AND RETROGRADE MOTIONS OF THE PLANETS. 



In the above cut Venus and the Earth mar be seen in their respective orbits, 
revolving eastward around the Sun. The arrows indicate the direction. Be- 
yond the orbits of the planets may be seen the concave circle of the starry heav- 
ens, and the constellations of the Zodiac. When Venug is at A, and has her 
greatest elongation earthward, her motion for a short time is almost always 
directly towards the Earth; so that she seems neither to recede from nor ap- 
proach the Sun. She is then said to be stationary. While passing from A to 
B, her apparent motion is retrograde, that is, westward among the stars; at B 
she again seems to be stationary for a time. 

From this point around to A again, her motion is direct, or eastward among 
the stars. She then seems to pass from C to D, as the arrow indicates her 
course through the heavens. 

From this diagram the pupil will readily understand why 
her direct motion should continue much longer than her re- 
trograde, &c. 

When is her apparent motion quickest? "When does she appear stationary I When 
is she brightest ? How great ia her light at this tin&e j 



VENUS. 195 

If the orbit of Venus lay exactly in the plane of the Earth's 
orbit, she would pass centrally across the Sun's disc, like a 
dark round spot, at every inferior conjunction ; but as one 
half of her orbit lies about 3i° above the ecliptic, and the 
other half as far below it, she will always pass the Sun a 
very little above or below it, except when her inferior con- 
junction happens in, or near, one of her nodes ; in which 
case she will make a transit. [See cut and explanations, 
page 197, and also Plate /., of Atlas. 

This phenomenon, therefore, is of very rare occurrence : 
it can happen only twice in a century; because it is only 
twice in that time "that any number of complete revolutions 
of Venus, are just or nearly equal to a certain nnmber of the 
Earth's revolutions. 

The principle which was illustrated in predicting the transits of Mercury, ap- 
plies equally well to those of Venus: that is. we must find such sets of numbers, 
(representing complete revolutions of the Earth and Venus.) as shall be to each 
other in the ratio of their periodical times, or as 365. 256 is to 224.7. Thus; the 
motion of Venus, in the Julian years, is 2106591". 52 ; that of the Earth for the 
same period being 129627".45, the ratio will be VAVW ^ 'H' ^ tne two 
terms of this fraction cannot be reduced by a common divisor, we must multiply 
them by such numbers as will make one a multiple of the other ; accordingly, 
13 times the denominator will be nearly equal to 8 times the numerator; and 475 
times the denominator will equal 291 t'imes the numerator. 

By combining these two periods and their multiples by addition and subtrac- 
tion, we shall obtain the period of all the transits that have ever happened. 
Thus; 291 — SX~=23o\ another period; and 291 — 6X$ = 243, another period, 
and so on. Whence we find that. 

8 periodical revolutions of the Earth, are equal to 13 of Venus. 

235 periodical revolutions of the Earth, are equal to 352 of Venus. 

243 periodical revolutions of the Earth, are equal to 395 of Venus. 

251 periodical revolutions of the Earth, are equal to 405 of Venus. 

291 periodical revolutions of the Earth, are equal to 475 of Venus. 

Hence a transit of Venus may happen at the same node, alter an interval ot 
8 years ; but if it do not happen then, it cannot take place again at the same 
node, in less than 235 years. The orbit of Venus crosses the ecliptic near the 
middle of Gemini and Sagittarius ; and these points mark the position of her 
nodes. At present, her ascending node is in the 14th degree of Gemini, and 
her descending node, in the same degree of Sagittarius. 

The Earth passes her ascending node in the beginning of 
December, and her descending; node, in the beginning of 
June. Hence, the transits of Venus, for ages to come, will 
happen in December and June. The first transit ever known 
to have been seen by any human being, took place at the 
ascending node, December 4th, 1639.* If to this date, we 

* This phenomenon was first witressed by Horrox. a young gentleman about 21 
years of age, living in an obscure village 15 miles north of Liverpool. The tables of 

Why does not Venus pass centrally across the Sun's disc at every inferior conjunc- 
tion ) In what ciicumstances wiil she make a transit across the Sun) How often 
can this phenomenon happen? Why can it not happen oriener? State the method 
of predicting the transits of Venus. After how long an interval may a transit of 
Venus happen again at thr. same node i If it do not happen then, how long a period 
must elapse before it irill occur again ot the same node/ Where does the orbit of 
Venus cross ti,e ecliptic, and where arc l>tr nodes? In what months, forages to 
come, will the transits, of Venus happen, and why? At which node, and when, did 
Uie first transit of Venus ever known to have been observed, take place ? 



196 VENUS. 

add 235 years, we shall have the time of the next transit at 
the same node, which will accordingly happen in 1874. There 
will be another at the same node in 1882, eight years after- 
wards. It is not more certain that this phenomenon will 
recur, than that the event itself will engross the attention of 
all the astronomers then living upon the Earth. It will be 
anticipated, and provided for, and observed, in every inhab- 
ited quarter of the globe, with an intensity of solicitude which 
no natural phenomenon, since the creation, has ever excited. 
The reason why a transit of Venus should excite so great 
an interest, is, because it may be expected to solve an im- 
portant problem in astronomy, which has never yet been 
satisfactorily done: — a problem whose solution will make 
known to us the magnitudes and masses of all the planets, 
the true dimensions of their orbits, their rates of motion 
around the Sun, and their respective distances from the Sun, 
and from each other. It may be expected, in short, to furnish 
a universal standard of astronomical measure. Another 
consideration will render the observation of this transit pe- 
culiarly favorable ; and that is, astronomers will be supplied 
with better instruments, and more accurate means of obser- 
vation, than on any former occasion. 

So important, says Sir John Herschel, have these observations appeared to 
astronomers, that at the last transit of Venus, in 1769, expeditions were fitted 
out, on the most efficient scale, by the British, French, Russian, and other 
governments to the remotest corners of the globe, for the express purpose of 

Kepler, constructed upon the observations of Tyrho Brahe, indicated a transit of Ve- 
nus in 1631, but none was observed. Horrox, without much assistance from books 
and instruments, set himself to inquire into the error of the tables, and found thai 
such a phenomenon might be expected to happen in 1639. He repealed his calcula- 
tions during this interval, with all the carefulness and enthusiasm of a scholar ambi- 
tious of being the first to predict and observe a celestial phenomenon, which, from the 
creation of the world, had never been witnessed ' Confident of the result, he commu- 
nicated his expected triumph to a confidential friend residing in Manchester, and desired 
him to watch for the event, and to take observations. So anxious was Horrox not to 
fail of witnessing it himself, that he commenced his observations the day before it was 
expected, and resumed them at the rising of the Sun on the morrow. But the very 
hour when his calculations led him to expect the visible appearance of Venus on the 
Sun's disc, was also the appointed hour for the public worship of God on the Sabbath. 
The delay of a few minutes might deprive him forever of an opportunity of observing 
the transit. If its very commencement were not noticed, clouds might intervene, and 
•onceal it until the Sun should set: and nearly a century and a half would elapse before 
another opportunity would occur. He had been waiting for the event with the most 
ardent anticipation for eight years, and the result promised much benefit to the science. 
Notwithstanding all this, Horrox twice suspended his observations, and twice repaired 
to the house of God, the Great Author of the bright works he delighted to contemplate. 
When his duty was thus performed, and he had returned to his chamber the second time, 
his love of science was gratified with full success ; and he saw what no mortal eye had 
observed before ! 

If any thing can add interest to this incident.it is the modesty with which the young 
astronomer apologizes to the world, for suspending his observations at all. 

" I observed it,'" says he, " from sunrise till nine o'clock, again a little before ten, and 
lastly at noon, and from one to two oclock ; the lest of the day being devoted to higher 
duties, which might not be neglected for these pastimes." 

When will the two next transits occur? Why will the next transit excite a very 
^reatand universal interest? Uron what do the phenomena of the seasons of each 
of the planets depend ? What is the estimated inclination of the axis ot Venus to the 
plane of her orbit? 



VENUS. 197 

makinz them. The celebrated expedition of Captain Cook to Otaheite. was one 
of them. The general result of all the observations made on this most memo- 
rable occasion, gives S".5776 for the Sun's horizontal parallax. 

The phenomena of the seasons of each of the planets, 
like those of the Earth, depend upon the inclination of the 
axis of the planet to the plane of its orbit, and its revolution 
around the sun. The inclination of the axis of Venus to the 
plane of her orbit, though not precisely known, is commonly 
estimated at 75°, as represented to the eye in the following 
cut: 



INCLINATION OF VENUS' AXIS. v en u3 



\ 




s of yenaf_PrbJ.t-_ 



J>laue of tke Ecliptio 



This is more than three times as great as the inclination 
of the Earth's axis to the plane of the ecliptic. 

The declination of the Sun on each side of her equator, 
must be equal to the inclination of her axis ; and if this ex- 
tends to 75°, her tropics T.T, are only 15° from her poles., 
and her polar circles P,P, only 15° from her equator. It 
follows, also, that the Sun must change his declination more 
in one day at Venus, than in five days on the Earth; and 
consequently, that he never shines vertically on the same 
places for two days in succession. This may perhaps be 
providentially ordered, to prevent the too great effect of the 
Sun's heat, which, on the supposition that it is in inverse 
proportion to the square of the distance, is twice as great on 
this planet as it is on the Earth. 

At each pole, the Sun continues half a j^ear* without set- 
ting in summer, and as long without rising in winter; con- 
sequently, the polar inhabitants of Venus, like those of the 
Earth, have only one day and one night in the year ; with 
this difference, that the polar days and nights of Venus art 
not quite two-thirds as long as ours. 

Between her polar circles, which are but 15° from he 
equator, there are two winters, two summers, two springs. 

* That is, halfof Venus' year, or 16 weeks. 

How does this inclination compare with that of the Earth's axis to the plane of the 
ecliptic? What seasons have the northern parts of Venus, when those of the Eanh 
have winter? How do we know this' To what must the declination of the Sun on 
each side of her equator be equal ? How far are her tropics from her poles, and her 
polar circles from her equator? How much more must the Sun change his deeiinn- 
tion in one day at Venus than on the Eanh ? Why. perhaps, is this so ordered • How 
many days and nights have her polar inhabitants (luring the year ? How Ion? are the-' 
days and nights, compared with those of our polar inhabitants? How many, c J 
what seasons, has Venus between her polar circles J 

17* 



198 VENUS. 

and two autumns, every year. But because the Sun stays 
for some time near the tropics, and passes so quickly over 
the equator, the winters in that zone will be almost twice as 
long as the summers. 

The north pole of Venus' axis inclines towards the 20th 
degree of Aquarius ; the Earth's towards the beginning of 
Cancer; consequently, the northern parts of Venus have 
summer in the signs where those of the Earth have winter, 
and vice versa. 

TELESCOPIC APPEARANCES OF VENUS. 




When viewed through a good telescope, Venus exhibits 
not only all the moon-like phases of Mercury, but also a va- 
riety of inequalities on her surface; dark spots, and brilliant 
shades, hills, and valleys, and elevated mountains. But on 
account of the great density of her atmosphere, these ine- 
qualities are perceived with more difficulty than those upon 
the other planets. 

The mountains of Venus, like those of Mercury and the 
Moon, are highest in the southern hemisphere. According 
to M. Schroeter, a celebrated German astronomer, who 
spent more than ten years in observations upon this planet, 
some of her mountains rise to the enormous height of from 
10 to 22 miles.* The observations of Dr. Herschel do not 
indicate so great an altitude ; and he thinks, that in general 
they are considerably overrated. He estimates the diameter 
of Venus at 8,649 miles ; making her bulk more than one 
sixth larger than that of the Earth. Several eminent as- 

* 1st, 22.05 miles ; 2d, 18.97 miles ; 3d, 11.44 miles ; 4th, 10.84 miles. 



What is the length «f the winters in this zone, compared with that of the summers? 
What appearances, besides her moon like phases, does Venus exhibit when seen 
through a good telescope? Why is it more difficult to perceive the inequalities on her 
surface than those on the other planets? In which hemisphere are her mountains 
highest? What does M. Schroeter make the altitude of some of the highest? Is this 
estimate confirmed by the observations of Dr Herschel ' How long is the diameter of 
Venus according to Herschel's estimate? How much larger, then, mu»t the be than 
the Earth ? 



THE EARTH. 



199 



tronomers affirm, that they have repeatedly seen Venus at- 
tended by a satellite, and they have given circumstantial 
details of its size and appearance, its periodical revolution 
and its distance from her. It is said to resemble our Moon 
in its phases, its distance, and its magnitude. Other astro- 
nomers deny the existence of such a body, because it was 
not seen with Venus on the Sun's disc, at the transits of 
1761 and 1769. 



TPIE EARTH. 



The Earth is the place from which all our observations 
of the heavenly bodies must necessarily be made. The ap- 
parent motions of these bodies being very considerably af- 
fected by her figure, motions, and dimensions, these hold an 
important place in astronomical science. It will therefore 
be proper to consider, first, some of the methods by which 
they have been determined. 

If, standing on the sea-shore, in a clear day, we view a 
ship leaving the coast, in any direction, the hull or body of 
the vessel first disappears ; afterwards the rigging, and lastly 
the top of the mast vanishes from our sight. 

CONVEXITY OF THE EARTH. 




Those on board the ship, observe that the coast first sinks 
below the horizon, then the buildings, and lastly the tallest 
spires of the city which they are leaving. Now these phe- 
nomena are evidently caused by the convexity of the water 
which is between the eye and the object ; for, were the sur- 
face of the sea merely an extended plane, the largest objects 
w T ould be visible the longest, and the smallest disappear first 

Another proof of the convexity of the earth's surface is, 
that the higher the eye is raised, the farther is the view ex- 
tended. An observer may see the setting sun from the top 

Some astronomers affirm thnt (hey have seen Venus attended by a satellite, why do 
Others deny the existence of such a body? Why is it important, in an astronomical 
view, to be acquainted with the tixure. dimensions, and motions of the Earth? Mention 
some of the proofs of the convexity of its surface .' Whojirst sailed around the Ecrth? 



200 THE EARTH. 

of a house, or any considerable eminence, after he has ceased 
to be visible to those below. 

Again: navigators have sailed quite around the Earth, 
and thus proved its convexity. 

CONVEXITY OF THE EARTH'S SURFACE. 




Ferdinand Magellan, a Portuguese, was the first who earned this enterprise 
into execution. He embarked from Seville, in Spain, and directed his course 
towards the west. After a long voyage, he descried the continent of America. 
Not finding an opening to enable him to continue his course in a westerly direc- 
tion, he sailed along the coast towards the south, till, coming to its soulhern ex- 
tremity, he sailed around it, and found himself in the great Southern Ocean. 
He then resumed his course towards the west. After some time he arrived at 
the Molucca Islands, in the Eastern Hemisphere; and sailing continually to- 
wards the west, he made Europe from the east; arriving at the place from 
which he set out * 

The next who circumnavigated the Earth, was Sir Francis Drake, who sailed 
from Plymouth, December 13. 1577. with five small vessels, and arrived at the 
same place, September 26, 1580. Since that time, the circumnavigation of the 
Earth has been performed by Cavendish, Cordes, Noort, Sharten, Heremites, 
Dampier, Woodes, Rogers, Schovten, Roggewin, Lord Anson, Byron, Carte- 
ret, Wallis, Bougainville, Cook. King, Clerk, Vancouver, and many others. 

These navigators, by sailing in a westerly direction, al- 
lowance being made for promontories, &c. arrived at the 
country they sailed from. Hence the Earth must be either 
cylindrical or globular. It cannot be cylindrical, because, if 
so, the meridian distances would all be equal to each other, 
which is contrary to observation. The figure of the Earth 
is. therefore, spherical. 

The convexity of the Earth, north and south, is proved by 
the variation in the altitude of the pole, and of the circumpo- 

* Magellan sailed from Seville, in Spain, August 10, 1519, in the ship called the Vic- 
tory, accompanied by four other vessels. In April, 1521, he was killed in a skirmish 
with the natives, at the island of Sebu, or Zebu, sometimes called Matan, one of the 
Philippines. One of his vessels, however, arrived at St. Lucar, near Seville, Septem- 
ber 7, 15-22. 

Describe briefly his voyage. Who next circumnavigated the E.arth't Describe hi* 
voyage? Mention the names of some of those who have since accomplished this enter- 
prise. What may we infer from these facts in regard to the figure of the Earth ? 



THE EARTH. 201 

lar stars, this is found uniformly to increase as we approach 
them, and to diminish as we recede from them. 

LATITUDE FOUND BY THE NORTH STaR. 




North star invisible. 

1l 



Suppose an observer standing upon the Earth, and viewing 
the pole star from the 45° of North latitude ; it would of 
course appear elevated 45° above his visible horizon. But 
let him recede southward, and as he passed over a degree 
of latitude, the pole star would settle one degree towards the 
horizon, or more properly, his northern horizon would be 
elevated one degree towards the pole star, till at length, as 
he crossed the equator, the North star would sink below the 
horizon, and become invisible. Whence we derive the gene- 
ral rule, that the altitude of one pole, or the depression of tlie 
other, at any place on the EarMs surface, is equal to the 
latitude of that place. 

The form of the Earth's shadow, as seen upon the Moon 
in an eclipse, indicates the globular figure of the earth, and 
the consequent convexity of its surface. 

FORM OF THE EARTh'3 SHADOW. 




202 



THE EARTH. 



Were the Earth a cube, as shown at A, or in the form of 
a prism, as represented at B, her shadow would be more 
or less cubical or prismatic, as seen in the cut; but instead 
of* this, it is convex on all sides, as represented at C, plainly 
indicating the convexity of the Earth by which it is caused. 

The curvature of the Earth for one mile is 8 inches ; and this curvature in- 
creases with the square of the distance. From this general law it will be easy 
to calculate the distance at which any object whose height is given, may be seen, 
or to determine the height of an object when the distance is known. 

1st. To find the height of the object when the distance is given. 

Rule. Find the square of the distance in miles, and take two-thirds of that 
number for the height in feet. 

Ex. 1.— How high must the eye of an observer be raised, to see the surface of 
the ocean, at the distance of three miles'? Ans. The square of 3 ft. is 9 ft., and 
§ of 9 ft. is 6 ft. Ex. 2.— Suppose a person can just see the top of a spire over 
an extended plain of ten miles, how high is the steeple 1 Ans. The square of 
10 is 100. and § of 100 is 66|, feet. 

2. To find the distance when the height is given. 

Rule. Increase the height in feet one half, and extract the square root, for 
the distance, in miles. 

Ex. 1.— How far can a person see the surface of a plain, whose eye is elevated 
six feet above it 7 Ans. 6, ii af-ed by its half, is 9, and the square root of 9 is 
3 ; the distance is then 3 m .» Ex. 2.— To what distance can a person see a 
light-house whose height is 9o icet from the level of the ocean? Ans. 96 in- 
creased by its half, is 144, and the square root of 144, is 12; the distance is 
therefore 12 miles. 

3. To find the curvature of the Earth when it exceeds a mile. 
Rule. Multiply the square of the distance by .000126. 

Although it appears from the preceding facts, that the 
Earth is spherical, yet it is not a perfect sphere. If it were, 
the length of the degrees of latitude, from the equator to the 
poles, would be uniformly the same ; but it has been found, 
by the most careful measurement, that as we go from the 
equator towards the poles, the length increases with the lati- 
tude. 

These measurements have been made by the most eminent mathematicians 
of different countries, and in various places, from the equator to the arctic cir- 
cle. They have found that a degree of latitude at the arctic circle was nine six- 
teenths of a mile longer than a degree at the equator, and that the ratio of in- 
crease for the intermediate degrees was nearly as the squares of the sines of the 
latitude. Thus the theory of Sir Isaac Newton was confirmed, that the body of 
the Earth was more rounded and convex between the tropics, but considerably 
flattened towards the poles. 



Places of 
Observation. 


Latitude. 


Length of a degree 
in English miles. 


Observers. 


Peru 

Pennsylvania 

Italy 

France 

England 

Sweden 


Equator. 
39° 12' N. 
43 01 
46 

51 29' 54." 
G6 20 10' 


68.732 
63.896 
68.998 
69.054 
69.146 
69-292 


Bouguer, 

Mason and Dixon, 

Boscovich and Lemaire, 

Delambre and Mechain, 

Madge, 

Swamberg. 



How is the convexity of her surface proved ? To what is the. convexity proportional? 
State the. rule, deduced from this fact, for finding the height of an olject, when its 
distance from us is given. State the rule for finding the distance when the height U 
given. State the. rule for finding the curvature of the F.arth wh^n the distance exceed* 
a mile. U ihe figure of the Earth an exact sphere ? Were the Eirth a perfect sphere, 
how would the length of the degrees of latitude be : compared with each other; How 
are tehy, in laoi 




THE EARTH. 203 

These measurements prove the Earth to be an oblate 
spheroid, whose longest or equatorial diameter is 7924 miles, 
and polar diameter, 7898 miles. The mean diameter is, 
therefore, about 7912, and their difference 26 miles. The 
French Academy have determined that the mean diameter 
of the Earth, from the 45th degree of north latitude, to the 
opposite degree of south latitude, is accurately 7912 miles. 

If the earth were an exact sphere, its diameter might 
be determined by its curvature, from a single measure- 
ment. Thus, in the adjoining figure, we have A B 
equal to 1 mile, and B D equal to 8 inches, to find A E, 
or B E, which does not sensibly differ from A E. since 
B D is only 8 inches. Now it is a proposition of Euclid, 
(B. 3, prop. 36.) that, when from a point without a circle, 
two lines be drawn, one cutting and the other touching 
it, the touching line (B A) is a mean proportional between 
the cutting line (B E) and that part of it (B D) with- 
out the circle. 

BD: BA:: BEorAE very nearly. 

That is, 1 mile beiwr equal to 63360 inches, 

8 : 43360 : : 63360 : 50181120 inches, or 7920 miles. 

This is very nearly what the most elaborate calculations make the Earth's 
equatorial diameter. 

The Earth, considered as a planet, occupies a favored 
rank in the Solar System. It pleased the All-wise Creator 
to assign its position among the heavenly bodies, where 
nearly all the sister planets are visible to the naked eye. It 
is situated next to Venus, and is the third planet from the Sun. 

To the scholar who for the first time takes up a book on astronomy, it will no 
doubt seem strange to find the Earth classed with the heavenly bodies. For 
what can appear more unlike, than the Earth, with her vast andseemingly im- 
measurable extent, and the stars, which appear but as points? The Earth is 
dark and opaque, the celestial bodies are brilliant. We perceive in it no motion ; 
while in them we observe a continual change of place, as we view them at dif- 
ferent hours of the day or night, or at different seasons of the year. 

It moves round the Sun, from west to east, in 365 days 
5 hours, 4S minutes, and 48 seconds; and turns, the same 
way. on its axis, in 23 hours, 56 minutes, and 4 seconds. 
The former is called its annual motion, and causes the vi- 
cissitudes of the seasons. The latter is called its diurnal 
motion, and produces the succession of day and night. 

The Earth's mean distance from the Sun is about 95 mil- 
lions of miles. It consequently moves in its orbit at the mean 

What is the length of a degree at the Arctic circle, compared toith a degree at the 
equator, as found "by the measurement of different mathematicians? What have they 
found to he the ratio of increase for the intermediate degrees ? What theory do these 
facts confirm I What is the length of the Earih's equatorial diameter, as found by 
these measurements ? What, her polar diameter? What is the difference between 
the two i What is her mean diameter? What have the French academy determined 
to be the exact mean diameter from the 45th degree of north latitude to the opposite 
decree of south latitude ? Illustrate the method, of finding the diameter if the Earth 
from her curvature, on the supposition that her figure is an exact sphere. What is 
the length of her diameter as thus found f IIoio is this, compared icith the equatorial 
diameter, as found by the most elaborate calculations? What is the position of tho 
Earth in the Solar System ? What revolutions does it perform, and in what direction ? 
the time occupied in each of these revolutions? By what terms are lb-;:.*, 
revolutions distinguished, and what important etfects do they produce ! 



204 THE EARTH. 

rate of 6S thousand miles an hour. Its equatorial diameter 
being 7924 miles, it turns on its axis at the rate of 1040 miles 
an hour. 

Thus, the Earth on which we stand, and which has served 
for ages as the unshaken foundation of the firmest structures, 
is every moment turning swiftly on its center, and, at the 
same time, moving onwards with great rapidity through the 
empty space. 

This compound motion is to be understood of the whole 
Earth, with all that it holds within its substance, or sustains 
upon its surface — of the solid mass beneath, of the ocean 
which flows around it, of the air that rests upon it, and of 
the clouds which float above it in the air. 

That the Earth, in common with all the planets, revolves 
around the Sun as a center, is a fact which rests upon the 
clearest demonstrations of philosophy. That it revolves, like 
them, upon its own axis, is a truth which every rising and 
setting sun illustrates, and which very many phenomena 
concur to establish. 

Either the Earth moves around its axis every day, or the 
whole universe moves around it in the same time. There is 
no third opinion, that can be formed on this point. Eithei 
the Earth must revolve on its axis every 24 hours, to pro- 
duce the alternate succession of day and night, or the Sun, 
Moon, planets, comets, fixed stars, and the whole frame of 
the universe itself, must move around the Earth, in the same 
time. To suppose the latter case to be the fact, would be to 
cast a reflection on the wisdom of the Supreme Architect, 
whose laws are universal harmony. As well might the 
beetle, that in a moment turns on its ball, imagine the heav- 
ens and the earth had made a revolution in the same instant. 
It is evident, that in proportion to the distance of the celes- 
tial bodies from the Earth, must, on this supposition, be the 
rapidity of their movements. The Sun, then, would move 
at the rate of more than four hundred thousand miles in a 
minute; the nearest stars, at the inconceivable velocity of 
1400 millions of miles in a second; and the most distant 
luminaries, with a degree of swiftness which no numbers 
could express, and all this, to save the litlte globe we tread 
upon, from turning safely on its axis once in 24 hours. 

The idea of the heavens revolving about the Earth, is en 
cumbered with innumerable other difficulties. We will men- 
tion only one more. It is estimated on good authority, that 
there are visible, by means of glasses, no less than one hun- 

What is the Earths mean distance from the Sun 7 What is the mean rate of iU 
motion in its orbit per hour ? What is the rate of its revolution on it* axis per hour 7 
What are the proofs, that it performs 'fcese two revolutions 7 



THE EARTH. 205 

dred millions of stars, scattered at all possible distances in 
the heavens above, beneath, and around us. Now, is it in 
the least degree probable, that the velocities of all these 
bodies should be so regulated, that, though describing circles 
so very different in dimensions, they should complete their 
revolutions in exactly the same time ? 

In short, there is no more reason to suppose that the heav- 
ens revolve around the Earth, than there is to suppose that 
they revolve around each ol the other planets, separately, 
and at the same time; since the same apparent revolution is 
common to them all, for they all appear to revolve upon 
their axes, in different periods. 

The rotation of the Earth determines the length of the 
day, and may be regarded as one of the most important ele- 
ments in astronomical science. It serves as a universal 
measure of time, and forms the standard of comparison f*r 
the revolutions of the celestial bodies, for all ages,. past and 
to come. Theory and observation concur in proving, that 
among the innumerable vicissitudes that prevail throughout 
creation, the period of the Earth's diurnal rotation is immu- 
table. 

The Earth performs one complete revolution on its axis 
in 23 hours, 56 minutes, and 4.09 seconds, of solar time. This 
is called a sidereal day, because, in that time, the stars 
appear to complete one revolution around the Earth. 

But as the Earth advances almost a degree eastward in 
its orbit, in the time that it turns eastward around its axis, it 
is plain that just one rotation never brings the same meri- 
dian around from the Sun to the Sun again; so that the 
Earth requires as much more than one complete revolution 
on its axis to complete a solar day, as it ha3 gone forward 
in that time. 

The diagram in the following page will explain the differ- 
ence between a solar and a sidereal revolution of the Earth. 

SOLAR AND SIDEREAL DAYS. 

The projections from the Earth's surface at four different 
points, indicate four meridians 90° apart. At A one is seen 
directly under the Sun, so that his light strikes it perpendic- 
ularly. At the same time the meridian B, is directly under 
or opposite the star C. But the Earth advances from this 
point to D, and at the same time revolves upon its axis till 
the meridian B again comes round opposite the star, as 
shown at E. At this time, however, the meridian A or F 






"VThat important purposes does the period of the Earth's rotation serve ? Vhat is a 
•idereal day ? What is a solar day l 

18 



206 



THE EARTH. 



*c 




is not yet opposite the Sun, but opposite the point G, just 
as much west of the Sun, as the Earth has gone eastward 
in her orbit. It is obvious, therefore, that in every natural 
or solar day, the Earth performs one complete revolution on 
its axis, and the 365th part of another revolution. Conse- 
quently, in 365 days, the Earth turns 366 times around its 
axis. And as every revolution of the Earth on its axis com- 
pletes a sidereal day, there must be 366 sidereal days in a 
year. And, generally, since the rotation of any planet about 
its axis is the length of a sidereal day at that planet, the 
number of sidereal days will always exceed the number of 
solar days, by one, let that number be what it may. one re- 
volution being always lost in the course of an annual revo- 
lution. This difference between the sidereal and solar days 
may be illustrated by referring to a watch or clock. "When 
both hands set out together, at 12 o'clock for instance, the 
minute hand must travel more than a whole circle before it 
will overtake the hour hand, that is, before they will come 
Into conjunction again. 

In the. same manner, if a man travel around the Earth 
eastwardly, no matter in what time, he will reckon one day 
more, on his arrival at the place whence he set out, than 
they do who remain at rest ; while the man who travels 
around the Earth westwardly will have one day less. From 
which it is manifest, that, if two persons start from the same 
place at the same time, but go in contrary directions, the 
one traveling eastward and the other westward, and each 
goes completely around the globe, although they should both 
arrive again at the very same hour at the same place from 



What part of a second revolution does the Earth complete in every solar day ? How 
many times, then, does it turn on its axis in i'65 days' How many sidereal days are 
th^ve in a year ? On any planet, what is the number of the sidereal days compared 
with the number of the solar' Illustrate the difference between the sidereal and 
solar days by referring to a watch or clock. Illustrate it by refemng to two travelers 
going around the globe, one eastw-jrdiy and the other westwardly. 



THE EARTH. 207 

which they set out, yet they will disagree two whole days 
in their reckoning. Should the day of their return, to the 
man who traveled westwardly, be Monday, to the man who 
traveled eastwardly, it would be "Wednesday; while to 
those who remained at the place itself, it would be Tuesday. 

Nor is it necessary, in order to produce the gain or less 
of a day, that the journey be performed either on the equa- 
tor, or on any parallel of latitude ; it is sufficient for the pur- 
pose, that all the meridians of the Earth be passed through, 
eastward or westward. The time, also, occupied in the 
journey, is equally unimportant; the gain or loss of a day 
being the same, whether the Earfh. be traveled around in 
24 years, or in as many hours. 

It is also evident, that if the Earth turned around its axis 
but once in a year, and if the revolution was performed the 
same way as its revolution around the Sun, there would be 
perpetual day on one side of it, and perpetual night on the 
other. 

From these facts the pupil will readily comprehend the principles involved in 
a curious problem which appeared a few years ago : It was gravely reported by 
an American ship, that, in sailing over the ocean, it chanced (o find six Sun- 
days in Februury. The fact was insisted on, and a solution demanded. 
There is nothing absurd in this. — The man who travels around the Earth east- 
wardly, will see the Sun go down a little earlier every succeeding day. than if he 
had remained at rest ; or earlier than t;iey do who live at the place from which 
he set out. The faster he travels towards the rising sun, the sooner will it appear 
above the horizon in the morning, and so much sooner will it set in the evening. 
What he thus gains in tune, will bear the same proportion to a solar day, as the 
distance traveled does to the circumference of ihe Earth.— As the globe is 360 
degrees in circumference, the Sun will appear to move over one twenty-fourth 
part of iis surface, or 14°, every hour, which is 4 minutes to one degree.— Con- 
Bequently, the Sun will rise, come to the meridian, and set, 4 minutes sooner, 
at a place 1° east of us, than it will with us ; at the distance of 2° the Sun will 
rise and set S minutes sooner; at the distance of 3°, 12 minutes sooner, and 
bo on. 

Now the man who travels one degree to the east, the first day will have the 
Sun on his meridian 4 minutes sooner than we do who are at rest ; and the 
second day 8 minutes sooner, and on the third day. 12 minutes sooner, and so 
on ; each successive day being completed 4 minutes earlier than the preceding, 
until he arrives again at the place from which he started: when this continual 
gain of 4 minutes a day will have amounted to a whole day in advance of -our 
time; he having seen the Sun rise and set once mure than we have. Conse- 
quently, the day on which he arrives at home, whatever day of the week it 
may be, is one day in advance of ours, and he must needs live (hat day over 
again, by calling the next day by the same name, in order to make the accounts 
harmonize. 

If this should be the last diy of February in a bissextile year, it would also be 
the same day of the week that the first was, and be six times repeated, and if it 
should happen on Sunday, he would, under these circumstances, have six 
Sundays in February. 

Again : — Whereas the man who travels at the rate of one degree to the east, 
will have all his days 4 minutes shorter than ours, so, on The contrary, the man 
who travels at the .-ame rate towards the west, will have all his days" 4 minutes 
longer \\\m\ ours. When lie has finished the circuit of the Earth, and arrived 

If the Earth revolved on its axis but once a year, and in the same direction as it re- 
volves around the Sun, what would be the consequence as it regards day and night? 
It was gravely reported some years ago by an American ship, that in sailing over the 
ocean, it found six Sundays in February; please explain this. 



208 



THE EARTH. 



at the place from which he first set out, he will have seen the Sun rise and set 
once less than we have. Consequently, the day he gets home will be one day 
after the time at that place : for which reason, if he arrives at home on Satur- 
day, according to his own account, he will have to call the next day Monday : 
Sunday having gone by before he reached home. Thus, on whatever day of the 
week January should end, in common years, he would find the same day re- 
peated only three times in February. If January ended on Sunday, he would, 
under these circumstances, find only three Sundays in February. 

The Earth's motion about its axis being perfectly equable 
and uniform in every part of its annual revolution, the side- 
real days are always of the same length, but the solar or 
natural days vary very considerably at different times of the 
year. This variation is owing to two distinct causes, the 
inclination of the Earth's axis to its orbit, and the inequality 
of its motion around the Sun. From these two causes it is, 
that the time shown by a well-regulated clock and that of a 
true sun-dial are scarcely ever the same. The difference 
between them, which sometimes amounts to 16^ minutes, is 
called the Equation of Time, or the equation of solar days. 

EQUATION OF TIME. 




The difference between mean and apparent time, or. in other words, between 
Equinoctial and Ecliptic time, may be further shown by this figure, which re- 
presents the circles of the sphere. Let it be first premised, that equinoctial 
time is clock time ; and that ecliptic time is solar or apparent time. It appears 
that from Aries to Cancer, the Sun in the ecliptic comes to the meridian before 
the equinoctial Sun : from Cancer to Libra, after it ; from Libra to Capricorn, 
before it ; and from Capricorn to Aries, after it. If we notice what months the 



Why are the sidereal days always of the same length' What are the causes of the 
difference in the length of the solar days ? What is meant by the expression, Equation 
of Time 1 Illustrate the difference between mean and apparent time by reference to 
the above figure. 




THE EARTH. 209 

Sun is in these several quarters, we shall find that from the 25th of December 
to the 16th of April, and from the 16th of June to the 1st of September, the 
clock is faster than the sun-dial : and that, from the 16th of April to the 16th 
of June, and from the 1st of September to the 25th of December, the sun dial 
is faster than the clock. 

It is a universal fact, that, while none of the planets are 
perfect spheres, none of their orbits are perfect circles. The 
planets all revolve about the Sun, in ellipses of different de- 
grees of eccentricity; having the Sun, not in the center of 
the ellipse, but in one of its foci. 

g The figure A D B E is an ellipse. The line 

A B is called the transverse axis, and the line 
drawn through the middle of this line, and 
perpendicular to it, is the conjugale axis. 
The point C, the middle of the transverse ax- 
is, is the center of the ellipse. The points F 
-yandf, equally distant from C, are called the 
foci. C F, the distance from the center to 
one of the foci, is called the eccentricity. 
The orbits of the planets being ellipses, having 
the Sun in one of the foci, if A D B E be the 
orbit of a planet, with the Sun in the locus F, 
q when the planet is at the point A, it will be in 

Its perihelion, or nearest the Sun ; and when at the point B in its aphelion, or at 
its greatest distance from the Sun. The difference in these distances is evidently 
equal to F f, that is. equal to twice the eccentricity of its orbit. In every revo- 
lution, a planet passes through its perihelion and aphelion. The eccentricity of 
the Earth's orbit is about one and a half millions of miles ; hence she is three 
millions of miles nearer the Sun in her perihelion, than in her aphelion. 

Now as the Sun remains fixed in the lower focus of the Earth's orbit, it is 
easy to perceive that a line, passins centrally through the Sun at right angles 
with the longer axis of the orbit, will divide it'lnto two unequal segments. Pre- 
cisely thus it is divided by the equinoctial. 

That portion of the Earth's orbit which lies above the Sun, 
or north of the equinoctial, contains about 184 degrees ; 
while that portion of it which lies below the Sun, or south 
of the equinoctial, contains only 176 degrees. This fact 
shows why the Sun continues about 8 days longer on the 
north side of the equator in summer, than it does on the 
south side in winter. The exact calculation, for the year 
1830, is as follows : 

d. h. m. d. h. m. 
From the vernal equinox to the summer solstice, =92 21 19 ) -.^ n ig 
From the summer solstice to the autumnal equinox, = 93 14 1 \ v " 
From the autumnal equinox to the winter solstice, = 59 17 17 t ,-^ in oq 
From the winter solstice to the vernal equinox, = S9 1 13 \ ' 

Difference in favor of the north side, = 7 16 49 

The points of the Earth's orbit which correspond to its greatest and least dis- 
tances from the Sun, are called, the former the Apogee, and the latter the Peri- 
gee ; two Greek words, the former of which signifies from the Earth, and the 
latter, aliout the Earth. These points are also designated by the common name 
of Apsides. [See these points represented, Plate I.] 

What is the figure of the orbits of the planets 7 In what point of the orbits is the Sun 
situated? What is the eccentricity of an orbit? How many limes is a planet in its 
aphelion, and how many in its perihelion, inevery revolution ? How much farther is it 
from the. Sun in the former case than in the latter? in ichich focus of the Earth's orbit 
is tlx Sw> ? How does the equinoctial divide the Earth's orbit? Why does the Sun 
remain longer on the north side of the i;qu;itor in summer, than it does on the south 
side in winter ? What are the Earths Apogee and Perigee? By w/iat common name 
are these two points designated? 

18* 



210 THE MOON. 

The Earth being in its perihelion about the 1st of January, 
and in its aphelion the 1st of July, we are three millions of 
miles nearer the Sun in winter than in midsummer. The 
reason why we have not. as might be expected, the hottest 
weather when the Earth is nearest the Sun, is, because the 
Sun, at that time, having retreated to the southern tropic, 
shines so obliquely on the northern hemisphere, that its rays 
have scarcely half the effect of the summer Sun; and con- 
tinuing but a short time above the horizon, less heat is ac- 
cumulated by day than is dissipated by night. 

As the Earth performs its annual revolution around the 
Sun, the position of its axis remains invariably the same ; 
always pointing to the North Pole of the heavens, and al- 
ways maintaining the same inclination to its orbit. This 
seems to be providentially ordered for the benefit of mankind. 
If the axis of the Earth always pointed to the center of its 
orbit, all external objects would appear to whirl about our 
heads in an inexplicable maze. Nothing would appear per- 
manent. The mariner could no longer direct his course by 
the stars, and every index in nature would mislead us. 



THE MOON. 



There is no object within the scope of astronomical obser- 
vation which affords greater variety of interesting inves- 
tigation than the various phases and motions of the Moon. 
From them the astronomer ascertains the form of the Earth, 
the vicissitudes of the tides, the causes of eclipses and oc- 
cultations, the distance of the Sun, and, consequently, the 
magnitude of the solar system. These phenomena, which 
are perfectly obvious to the unassisted eye, served as a stan- 
dard of measurement to all nations, until the advancement 
of science taught them the advantages of solar time. It is 
to these phenomena that the navigator is indebted for that 
precision of knowledge which guides him with well-grounded 
confidence through the pathless ocean. 

The Hebrews, the Greeks, the Romans, and, in general, 
all the ancients, used to assemble at the time of new or full 
Moon, to discharge the duties of piety and gratitude for her 

When is the Earth in its Perihelion? When in its Aphelion? Are we nearer the 
Sun in summer than in winter ? How much nearer are we in winter than in summer ? 
Why do we not have the hottest weather when we are nearest the Sun ? As the 
Earth revolves about the Sun, what is the position of its axis ? Should its axis alwayi 
point to the center of its orbit, how would external objects appear to us 3 What im- 
portant purposes does the Moon serve to the astronomer ? Of what importance are 
her phenomena to the navigator? What nations used to assemble at the time of the 
new or of the full Moon, to express their gratitude for her benefits 7 



THE MOON. 



211 



unwearied attendance on the Earth, and all her manifold 
uses. 

The philosophy of the changes of the Moon is illustrated 
by the following cut : 

PHILOSOPHY OF THE MOON'S CHANGES. 




When the Moon, after having been in conjunction with 
the Sun, emerges from his rays, she first appears in the 
evening, a little after sunset, like a fine luminous crescent, 
with its convex side towards the Sun. If we observe her 
the next evening, we find her about 13° farther east of the 
Sun than on the preceding evening, and her crescent of light 
sensibly augmented. Repeating these observations, we per- 
ceive that she departs farther and farther from the Sun, as 
her enlightened surface comes more and more into view, un- 
til she arrives at herjirst quarter, and comes to the meridian 
at sunset. She has then finished half her course from the 
new to the full, and half her enlightened hemisphere is turn- 
ed towards the Earth. 

After her first quarter, she appears more and more gib- 
bous, as she recedes farther and farther from the Sun, until 
she has completed just half her revolution around the Earth, 
and is seen rising in the east when the Sun is setting in the 
west. She then presents her enlightened orb full to our 
view, and is said to be in opposition; because she is then 
on the opposite side of the Earth with respect to the Sun. 

In the first half of her orbit she appears to pass over our 
heads through the upper hemisphere ; 6he now descends 
below the eastern horizon to pass through that part of her 
orbit which lies in the lower hemisphere. 

After her full she wanes through the same changes of ap- 

Describe the apparent motion of the Moon, and her phases. How is it known that 
the Moon does not shine by her own light? 



212 THE MOON. 

Eearance as before, but in an inverted order; and we see 
er in the morning like a fine thread of light, a little west of 
the rising-sun. For the next two or three days she is lost 
to our view, rising and setting in conjunction with the Sun; 
after which, she passes over, by reason of her daily motion, 
to the east side of the Sun, and we behold her again a new 
Moon, as before. In changing sides with the Sun, she 
changes also the direction of her crescent. Before her con- 
junction it was turned to the east ; it is now turned towards 
the west. These different appearances of the Moon are 
called her phases. They prove that she shines not by any 
light of her own; if she did, being globular, we should al 
ways see her a round full orb like the Sun. 

The Moon i3 a satellite to the Earth, about which she re- 
volves in an elliptical orbit, in 29 days, 12 hours, 44 minutes, 
and 3 seconds: the time which elapses between one new 
moon and another. This is called her synodic revolution. 
Her revolution from any fixed star to the same star again, 
is called her 'periodic or sidereal revolution. It is accom- 
plished in 27 days, 7 hours, 43 minutes, and 11| seconds; 
but in this time, the Earth has advanced nearly as many 
degrees in her orbit; consequently the Moon, at the end of 
one complete revolution, must go as many degrees farther, 
before she will come again into the same position with re- 
spect to the Sun and the Earth. 

SIDEREAL AND SYNODIC REVOLUTIONS OF THE MOON. 



jg _Sidf:T ^liJR ep otti tim^_^^ 



About what does the Moon revolve, and what is the figure of her orbit ? What is 
the time of her revolution from one new Moon to another? What is this revolution 
denominated? What ia her periodic or sidereal revolution? In what time is this 
accomplished ) 



THE MOON. 213 

To illustrate : When the Earth is at A, and the Moon at 
B, the latter is in conjunction with the Sun. While the Earth 
moves on from A to C, the Moon makes a complete revolu- 
tion around her, and reaches the point in her own orbit at D 
from which she started. But though she has now gone quite 
around the Earth, she is not now in conjunction with the 
Sun, as when at B, but must pass on from D to E, in order 
to come again in conjunction. It is obvious, therefore, that 
the Synodical exceeds the Sidereal revolution by the dis- 
tance from D to E, which is just equal in degrees to the dis- 
tance A C, in the Earth's orbit. This cut also shows why 
it takes 2 days and 5 hours longer for the Synodic than for 
the Sidereal revolution. 

The cause of this difference is the same as that producing 
a disagreement between the Solar and Sidereal day, illus- 
trated p. 206, namely, the advancement of the Earth in her 
orbit. 

The Moon is the nearest of all the heavenly bodies, being 
about 30 times the diameter of the Earth, or 240,000 miles, 
distant from us. Her mean daily motion, in her orbit, is 
nearly 14 times as great as the Earth's ; since she not only 
accompanies the Earth around the Sun every year, but, in 
the mean time, performs nearly 13 revolutions about the 
Earth. 

Although the apparent motion of the Moon in her orbit, is greater than that of 
any other heavenly body, since she passes over, at a mean rate, no less than 
13° 10' 35" in a day ; yet this is to be understood as angular motion, — motion 
in a small orbit, and therefore embracing a great number of degrees, and but 
comparatively few miles. 

As the Moon, while revolving about the Earth, is carried 
with it at the same time around the Sun, her path is ex- 
tremely irregular, and very different from what it seems to 
be. Like a point in the wheel of a carriage, moving over 
a convex road, the Moon will describe a succession of epicy- 
cloidal curves, which are always concave towards the Sun; 
not very unlike their presentation in the following figure.* 

* This cut is perpetuated, not because the Moon ever actually retrogrades, and 
crosses her own path, but because the figure conveys a tolerable general idea of the 
Moon's motions, and helps to a more ready and accurate understanding of the true 
lunar orbit. The truth, as hereafter shown, is that the Moon never actually retro- 
grades, and always moves in a path concave towards the Sun. 

To what is the difference of time in these two revolutions owing? How great is the 
distance of the Moon from the Earth, compared with that of the other heavenly bodies ? 
What is her distance from us? What is her motion in her orbit, compared with the 
Earth's ? How many times does she revolve around the Earth, every year? Tfie appa- 
rent motion of the Moon is greater in her orbit than that of any other heavenly body; 
is it to be understood that she passes through a correspondent space? Describe the 
Moon's path. 



214 



THE MOON. 
THE MOON'S MOTION. 




Let Ad b B represent a portion of the Earth's orbit ; and a b c d e the lunar 
orbit. When the Earth is at b, the new Moon is at a ; and while the Earth is 
moving from b to its position as represented in the figure, the Moon has moved 
through half her orbit, from a to c. where she is full ; so while the Earth is mov- 
ing from its present position to d, the Moon describes the other half of her or- 
bit from c to e ; where she is again in conjunction. 

The preceding, however, is by no means an accurate 
representation of the Moon's orbit, though it affords a good 
general idea of her path and revolutions. A better " Theory," 
as it is termed, will be found illustrated in Plate 1 of the At- 
las, but this also fails to exhibit the real orbit of the Moon. 
This is far more accurately shown in the following cut, in 
which the dark curve line represents the Earth's path, and 
the variable dotted line the orbit of the Moon. The cord 
A B extending from one crossing to another passes more 
than 400,000 miles from the Earth ; but as the Moon only 
departs 240.000 miles from us, it follows that her path must 
be concave towards the Sun, as shown in the figure, even 
while within the Earth's orbit. She must be more than 
400.000 miles from the Earth to describe an orbit in the least 
convex towards the Sun, at any time. 

The Moon, though apparently as large as the Sun, is the 
smallest of all the heavenly bodies that are visible to the 
naked eye. Her diameter is but 2162 miles; consequently 
her surface is 13 times less than that of the Earth, and her 
bulk 49 times less. It would require 70 millions of such 

What is her magnitude, compared with that of the other heavenly bodies 1 What 
is her diameter? How great a<e her surface and her bulk, compared with those of the 
Earth? How many such bodies would it require to equal the volume of the Sun? Why 
does she appear as large as the Sun, when in reality she is so much less ? 



THE MOON. 215 

bodies to equal the volume of the Sun. The reason why 
she appears as large as the Sun, when, in truth, she is so 
much less, is because she is 400 times nearer to us than the 
Sun. 

TRUE ORBIT OF THE MOON. 




The Moon revolves once on her axis exactly in the time 
that she performs her revolution around the Earth. This 
is evident from her always presenting the same side to the 
Earth ; for if she had no rotation upon an axis, every part 
of her surface would be presented to a spectator on the 
Earth, in the course of her synodical revolution. It follows, 
then, that there i3 but one day and night in her year, con- 
taining, both together, 29 days, 12 hours, 44 minutes, and 
3 seconds. 

As the Moon turns on her axis only as she moves around 
the Earth, it is plain that the inhabitants of one half of the 
lunar world are totally deprived of the sight of the Earth, 
unless they travel to the opposite hemisphere. This we 
may presume they will do. were it only to view so sublime 
a spectacle ; for it is certain that from the Moon the Earth 
appears ten times larger than any other body in the universe. 

As the Moon enlightens the Earth, by reflecting the light 
of the Sun, so likewise the Earth illuminates the Moon, ex- 
hibiting to her the same phases that she does to us, only in 
a contrary order. And, as the surface of the Earth is 13 
times as large as the surface of the Moon, the Earth, when 
full to the Moon, will appear 13 times as large as the full 
Moon does to us. That side of the Moon, therefore, which 

What is the time of her revolution on her nxis, compared with that of her revolutioi 
Wound the Earth ? How is this proved? How many Jays ami niirhts then has she ii 
the course of her synodical revolution? What is the length of both united? Describl 
Uie phenomena of the Earth as seen by the inhabitants of the Moon 



216 THE MOON. 

is towards the Earth, may be said to have no darkness at 
all, the Earth constantly shining upon it with extraordinary 
splendor when the Sun is absent ; it therefore enjoys suc- 
cessively two weeks of illumination from the Sun, and two 
weeks of earth-light from the Earth. The other side of the 
Moon has alternately a fortnight's light, and a fortnight's 
darkness. 

As the arth revolves on its axis, the several continents, 
seas, and islands, appear to the lunar inhabitants like so 
many spots, of different forms and brightness, alternately 
moving over its surface, being more or less brilliant, as they 
are seen through intervening clouds. By these spots, the 
lunarians can not only determine the period of the Earth's 
rotation, just as we do that of the Sun, but they may also 
find the longitude of their places, as we find the latitude of 
ours. 

As the full Moon always happens when the Moon is di- 
rectly opposite the Sun, all the full Moons in our winter, 
must happen when the Moon is on the north side of the equi- 
noctial, because then the Sun is on the south side of it; con- 
sequently, at the north pole of the Earth, there will be a 
fortnight's moon-light and a fortnight's darkness by turns, 
for a period of six months, and the same will be the fact du- 
ring the Sun's absence the other six months, at the south 
pole. 

The Moon's axis being inclined only about H° to her 
orbit, she can have no sensible diversity of seasons ; from 
which we may infer, that her atmosphere is mild and uni- 
form. The quantity of light which we derive from the Moon 
when full, is at least 300 thousand times less than that of the 
Sun.* 

When viewed through a good telescope, the Moon pre- 
sents a most wonderful and interesting aspect. Besides the 
large dark spots, which are visible to the naked eye, we 
perceive extensive valleys, shelving rocks, and long ridges 
of elevated mountains, projecting their shadows on the plains 
below. Single mountains occasionally rise to a great height, 

* This is Mons. Bouquer's inference, from his experiments, as stated by La Place, in 
his work, p. 42. The result of Dr. Wellaston's computations was different. Professor 
Leslie makes the light of the Moon 150,000 times less than that of the Sun : it was for- 
merly reckoned 100,000 times less. 

As the Earth revolves on its axis, how do its continents, seas, and islands, appear 
to the lunar inhabitants f For what purposes may these spots serve to the lunarians! 
What are the periods of the Moon's presence and absence to the polar inhabitants! 
Explain this. Why cannot the Moon have any sensible diversity of seasons? What 
then may we infer to be the character of her atmosphere ? What is the quantity of 
light which she affords when full, compared with that of the Sun ? Describe the ap- 
pearance of the Moon when seen through a good telescope. What mountains of the 
Earth does h«r mountain scenery resemble ? 



THE MOON. 2 k 

while circular hollows, more than thrte miles deep, seem 
excavated in the plains. 

TELESCOPIC VIEWS OF THE MOON. 




Her mountain scenery bears a striking resemblance to the 
towering sublimity and terrific ruggedness of the Alpine re- 
gions, or of the Apennines, after which some of her moun- 
tains have been named, of and the Cordilleras of our own 
continent. Huge masses of rock rising precipitously from 
the plains, lift their peaked summits to an immense "height 
in the air, while shapeless crags hang over their projecting 
sides, and seem on the eve of being precipitated into the 
tremendous chasm below. 

Around the base of these frightful eminences, are strewed 
numerous loose and unconnected fragments, which time 
seems to have detached from their parent mass j and when 
we examine the rents and ravines which accompany the 
overhanging cliffs, the beholder expects every moment that 
they are to be torn from their base, and that the process of 
destructive separation which he had only contemplated in 
its effects, is about to be exhibited before him in all its 
reality. 

The range of mountains called the Apennines, which tra- 
verses a portion of the Moon's disc from north-east to south- 
west, and of which some parts are visible to the naked eye, 
rise with a precipitous and craggy front from the level of 
the Mare Imbrium, or Sea of Showers.* In this extensive 
range are several ridges whose summits have a perpendicu- 
lar elevation of four miles, and more ; and though they often 
descend to a much lower level, they present an inaccessible 
barrier on the north-east, while on the south-west they sink- 
in gentle declivity to the plains. 

* The name of a lunar spot. 

Describe the appearance of her mountains. On what part of her disc is that r 
mountains called the Apennines, situated .' Describe it. What remarkable feature ia 
lh«i Moon's surface, bears no analogy to any thing observable on the Earth's surface: 

19 



218 THE MOON. 

There is one remarkable feature in the Moon's surface 
which bears no analogy to any thing observable on the 
Ea-th. This is the circular cavities which appear in every 
part of her disc. Some of these immense caverns are nearly 
four miles deep, and forty miles in diameter. They are 
most numerous in the south-western part. As they reflect 
the Sun's rays more copiously, they render this part of her 
surface more brilliant than any other. They present to us 
nearly the same appearance as our Earth might be supposed 
to present to the Moon, if all our great lakes and seas were 
dried up. 

The number of remarkable spots on the Moon, whose 
latitude and longitude have been accurately determined, 
exceeds 200. The number of seas and lakes, as they were 
formerly considered, whose length and breadth are known, 
is between 20 and 30; while the number of peaks and moun- 
tains, whose perpendicular elevation varies from a fourth of 
a mile to five miles in height, and whose bases are from one 
to seventy miles in length, is not less than one hundred and 
fifty.* 

Graphical views of these natural appearances, accompanied with minute and 
familiar descriptions, constitute what is called Selenography, from two Greek 
words, which mean the same thing in regard to the Moon, as Geography dots 
in regard to the Earth. 

An idea of some of these scenes may be formed by con- 
ceiving a plane of about 100 miles in circumference, encircled 
by a range of mountains, of various forms, three miles in 
perpendicular height, and having a mountain near the cen- 
ter, whose top reaches a mile and a half above the level of 
the plain. From the top of this central mountain, the whole 
plain, with all its scenery, would be distinctly visible, and 
the view would be bounded only by a Jolty amphitheatre of 
mountains, rearing their summits to the s^^ 

The bright spots of the Moon are the mountainous re- 
gions ; while the dark spots are the plains, or more level 
parts of Iter surface. There may be rivers or small lakes 

* Brewster's Selenography. The best maps of the Moon hitherto published, are 
those by Schroeter ; but the most, curious and complete representation ot the telescopic 
and natural appearances of the Moon, is to be seen in Russet's Lunar Globe, See also 
Selenographia, by C. Blunt. 

Describe their appearance. What is the number of remarkable spots on the Moon's sur 
face, whose latitude and longitude have been accurately determined? What is the num- 
ber of seas and lakes, as they were formerly considered, whose dimensions are known i 
What is the number of peaks and mountains whose perpendicular elevation varies 
from a fourth of a mile to five miles, and w hose bases are from one to seventy miles in 
length? What is Selenography? Give an illustration to enable us to lbrm some idea of 
eome of these scenes. Which spots are the mountainous regions, and which the plains? 
Do astronomers now suppose, as they did formerly, that there are large collections of 
water on the Moon's surface? Are any of her mountains and valleys visible to the 
naked eye? How small a spot on the Moon's surface ean be seen by a telescope which 
magnifies 100 tunes* 



SOLAR AND LUNAR ECLIPSES. 219 

on this planet; but it is generally thought, by astronomers 
of the present day, that there are no seas or large collections 
of water, as was formerly supposed. Some of these moun- 
tains and deep valleys are visible to the naked eye ; and 
many more are visible through a telescope of but moderate 
powers. 

A telescope which magnifies only 100 times, will show a 
spot on the Moon's surface, whose diameter is 1223 yards ; 
and one which magnifies a thousand times, will enable us 
to perceive any enlightened object on her surface whose di- 
mensions are only 122 yards, which does not much exceed 
the dimensions of some of our public edifices, as for instance, 
the Capitol at Washington, or St. Paul's Cathedral. • Pro- 
fessor Frauenhofer, of Munich, recently announced that he 
had discovered a lunar edifice, resembling a fortification, 
together with several lines of road. The celebrated as- 
tronomer Schroeter, conjectures the existence of a great 
city on the east side of the Moon, a little north of her equa- 
tor, an extensive canal in another place, and fields of vege- 
tation in another. 



SOLAR AND LUNAR ECLIPSES. 

Of all the phenomena of the heavens, there are none 
which engage the attention of mankind more than eclipses 
of the Sun and Moon ; and to those who are unacquainted 
with astronomy, nothing appears more wonderful than the 
accuracy with which they can be predicted. In the early 
ages of antiquity they were regarded as alarming deviations 
from the established laws of nature, presaging great public 
calamities, and other tokens of the divine displeasure. 

In China, the prediction and observance of eclipses are made a matter of 
state policy, in order to operate upon the fears of the ignorant, and impose on 
them a superstitious regard for the occult wisdom of their rulers. In Mexico, 
the natives fast and afflict themselves, during eclipses, under an apprehension 
that the Great Spirit is in deep sufferance. Some of the northern tribes of In- 
dians have imagined that the Moon had been wounded in a quarrel; and others, 
that she was about to be swallowed by a huge fish. 

It was by availing himself of these superstitious notions, that Columbus, 
when shipwrecked on the island of Jamaica, extricated himself and crew from 
a most embarrassing condition. Being driven to great distress for want of pro- 
visions, and the natives refusing him any assistance, when all hope seemed to 

How small an enlightened object can be seen by one which magnifies 1000 times? 
Mention any public edilices which are of nearly the same dimensions. How were 
eclipses regarded in the early ages of antiquity ) To what purpose do the rulers of China 
make their prediction and observance subservient 7 How do the natives of Mexico de- 
mean themselves during an eclipse ,' Why do they do this 1 What notions have some 
Of the northern tribes of Indians entertained icith regard to eclipses of the Moon t Re- 
late the anecdote of Columbus extricating himself and his crew from distress, by avail- 
w^ himself of the superstitious notions ofllie natives of Jamaica in regatd to eclipses. 



220 SOLAR AND LUNAR ECLIPSES. 

be cut off, he bethought himself of their superstition in regard to eclipses. 
Having assembled the principal men of the island, he remonstrated against 
their inhumanity, as being offensive to the Great Spirit : and told them that a 
great plague was even then ready to fall upon them, and as a token of it, they would 
that night see the Moon hide her face in anger, and put on a dreadfully dark 
and threatening aspect. This artifice had the desired effect ; for the eclipse had 
no sooner begun, than the frightened barbarians came running with all kinds of 
provisions, and throwing themselves at the feet of Columbus, implored his 
forgiveness. — Almagest, Vol. I. 55 c. v. 2. 

An eclipse of the Sun takes place, when the dark body of 
the Moon, passing directly between the Earth and the Sun, 
intercepts his light. This can happen only at the instant of 
new Moon, or when the Moon is in conjunction; for it is 
only then that she passes between us and the Sun. 

An eclipse of the Moon takes place when the dark body 
of the Earth, coming between her and the Sun, intercepts 
his light, and throws a shadow on the Moon. This can 
happen only at the time of full Moon, or when the Moon is 
in opposition ; for it is only then that the Earth is between 
her and the Sun. 

As every planet belonging to the solar system, both pri- 
mary and secondary, derives its light from the Sun, it must 
cast a shadow towards that part of the heavens which is 
opposite to the Sun. This shadow is of course nothing but 
a privation of light in the space hid from the Sun by the 
opaque body, and will always be proportioned to the magni- 
tude of the Sun and planet. 

If the Sun and planet were both of the same magnitude, 
the form of the shadow cast by the planet, would be that of 
a cylinder, and of the same diameter as the Sun or planet 

CYLINDRICAL SHADOW. 




If the planet were larger than the Sun, the shadow would 
continually diverge, and grow larger and larger; but as the 
Sun is much larger than any of the planets, the shadows 
which they cast must converge to a point in the form of a 
cone, the length of which will be proportional to the size 
and distance of the planet from the Sun. 

What causes eclipses of the Sun? What causes eclipses of the Moon? In what 
direction does every planet of the solar system cast a shadow ? What is this shadow, 
and to what is it proportional 1 If the Sun and planet were both of the same magnitude, 
what would be the form of the shadow, and its diameter? If the planet were larger 
than the Sun, what would be the form of the shadow ? But as the Sun is much larger 
than any of the planets, what must be the form of their shadows, and to what are they 
proportional? 



SOLAR AND LUNAR ECLIPSES. 221 

DIVERGING SHADOW. 





CONVERGING SHADOWS. 




The masnitude of the Sun Is such, that the shadow cast hy each of the pri- 
mary planets always converges to a point before it reaches any o:her planet ; so 
that not one of the primary planets can eclipse another. The shadow of anv 
planet which is accompanied by Satellites, may, en certain occasions, eclipse 
its satellites ; but it is not long enough to eclipse any other bodv. The shadow 
of a satellite or Moon, may also, on certain occasions, fall on the primary, 
and eclipse it 

When the Sun is at his greatest distance from the Earth, 
and the Moon at her least distance, her shadow is suffi- 
cientiy long to reach the Earth, and extend 19.000 miles 
beyond. When the Sun is at his least distance from the 
Earth, and the Moon at her greatest, her shadow will not 
reach the Earth's surface by 20.000 miles. So that when 
the Sun and Moon are at their mean distances, the cone of 
the Moon's shadow will terminate a little before it reaches 
the Earth's surface. 

In the former case, if a conjunction take place when the 
center of the Moon comes in a direct line between the cen- 
ters of the Sun and Earth, the dark shadow of the Moon 
will fill centrally upon the Earth, and cover a circular area 
of 175 miles in diameter. To all places lying within this 
dark spot, the Sun will be totally eclipsed, as illustrated by 
the figure. 



Why can no one of the primary planets eclipse another! Explain how, on certain 
occasions, they may eclipse their satellites, and on others be eclipsed by them. When 
the Sun is at his greatest distance from the Earth, and the Moon at her I eaxt distance, 
how far will her shadow extend ? When the Sun is at his least distanre, and the Moon 
at her greatest ' When the Sun and Moon are both at their itienn di-tances / In the 
first case, in what circumstances will the Moon's shadow full centrally on the Earth, 
and what will be its fieure and diameter i How will the Sun appear to all places lying 
within this dark Bpot ' Describe the effect of the Earth's motion, during ths eclipse, 
upon this circular area. 



19* 



222 SOLAR AND LUNAR ECLIPSES. 

ECLIPSES OF THE SUN. 




In consequence of the Earth's motion during the eclipse, this circular area 
becomes a continued belt over the Earth's surface ; being, at the broadest, 175 
miles wide. This belt is, however, rarely so broad, and often dwindles to a 
mere nominal line, without total darkness. 

In March, this line extends itself from S. W. toN. E., and in September, from 
N. W. to S. E. In June, the central line is a curve, going first to the N. E., 
and then to the S. E. ; in December, on the contrary, first to the S. E., and then 
to the N. E. To all places within 2000 miles at least of the central line, the 
eclipse will be visible; and the nearer the place of observation is to the line, the 
larger will be the eclipse. In winter, if the central trace be but a little north- 
ward of the equator, and in summer, if it be 25 degrees N. latitude, the eclipse 
will be visible all over the northern hemisphere. As a general rule, though lia- 
ble to many modifications, we may observe, that places from 200 to 250 miles 
from the central line, will be 11 digits eclipsed; from thence to 500 miles, 10 
digits ; and so on, diminishing one digit in about 250 miles. 

If. in either of the other cases, a conjunction take place 
when the Moon's center is directly between the centers of the 
Sun and Earth, as before, the Moon will then be too distant 
to cover the entire face of the Sun, and there will be seen, all 
around her dark body, a slender ring of dazzling light. 




This may be illustrated by the above figure. Suppose C D to represent a part 
of the Earth's orbit, and the Moon's shadow to terminate at the vertex V. ; the 
small space between e/will represent the breadth of the luminous ring which 
Will be visible all around the dark body of the Moon. 

The appearance and progress of an annular eclipse, is 
illustrated by the following cut, where the dark body of 



In either of the other cases, the same circumstances occurring as before, what will 
be the appearance of the Sun 1 Why does not the Moon, in this case, cause a total 
eclipse? When did the first eclipse of this kind, ever visible in the United States, hap- 
pen? How long did the luminous ring, along its path, remain unbroken! When 
did the next annular eclipse, visible to any considerable portion of the United States, 
happen? 



SOLAR AND LUNAR ECLIPSES. 223 

the Moon is seen resting upon the center of the Sun. and 
leaving a luminous ring unobscured. 

ECLIPSE OF THE SUN. 
Going off. Annular. Com 




Such was the eclipse of February, 12, 1331, which passed over the southern 
states, from S. W. to N. E. It was the first annular eclipse ever visible in the 
United States. Along the path of this eclipse, the luminous ring remained per- 
fect and unbroken for the space of two minutes. The last annular eclipse visi- 
ble to any considerable portion of the United States, took place Sept. 13th. 
1833. 

From the most elaborate calculations, compared with a long series of obser- 
vations, tlie length of the Moon's shadow in eclipses, and her distance from the 
San at the same time, vary within the limits of the following table : 



Length of Shadow, 
Dist. of Moon. 


Length of Shadow in 
Semidiameters. 


Lensth 
in miles. 


Distance in 
Semidiameters. 


Distance 
in miles. 


Least 

Mean 

Greatest 


57.760X3956= 
58.728X3956- 

59.730X3956= 


223.499 
232.323 
236,292 


55.902X3956= 
60.233X3956= 

63. 3-- X 3956= 


221.143 
233.300 
252.633 



Thus it appears that the length of the cone of the Moon's shadow, in eclipses, 
varies from 22S.499 to 236,292 miles ; being 7.793 miles longer in the one case, 
than in the other. The inequality of her distances from the Earth is much 
greater; they vary from 221.143 tb 252.633 miles, making a difference of 31,490 
miles. 

Although a central eclipse of the Sun can never be total 
to any spot on the Earth more than 175 miles broad ; yet 
the space over which the Sun will be more or less partially 
eclipsed, is nearly 5000 miles broad. 

The section of the Moon's shadow, or her penumbra, at the Earth's surface, 
in eclipses, is far from being always circular. If the conjunction happen when 
the center of the Moon is a little above or a little beloic the center of the line 
joining the centers of the Earth and Sun, as is most frequently the case, the 
shadow will be projected obliquely over the Earth's surface, and thus cover 
a much larger space. 

To produce a partial eclipse, it is not necessary that the shadow should reach 
the Earth; it is sufficient that the apparent distance between the Sun and 
Moon be not greater than the sum of their semidiameters. 

What are the limits between which the Moon's shadoto varies in eclipses! What is 
the difference between these trco limits 1 What are the limits of her distances from the 
Earth! What is the difference between them) What is the greatest breadth of any 
spot on the Earth's surtace, to which a central eclipse of the Sun can be total ? What 
is the breadth of the greatest space over which the Sun can be more or less partially 
eclipsed f Is the penumbra of the Moon at Vie Earth's surface in eclipses dways cir- 
cular! In ichat circumstances ic ill the siiadow be projected obliquely aver the Earth's 
surface? Must the shadoio reach the Earth, to produce a partial eclipse? What is 
the greatest apparent distance bctu-etn the *vn and Moon, within which ntch a result 
totil take place/ Why is not the Sun eclipsed at the time of every new Moon, and the 
Moon at every full? In what circumstances will an eclipse of the Sun. and in what au 
eclipse o! the Moon, huppen ? 



224 



SOLAP. AND LUNAR ECLIPSES. 



If the Moon performed her revolution in the same path in 
which the Sun appears to move; in other words, if her orbit 
lay exactly in the plane ol the Earth's orbit, the Sun would 
be eclipsed at the time of every new Moon, and the Moon 
at the time of every full. But one half of the Moon's orbit 
lies about 5° on the north side of the ecliptic, and the other 
half as far on the south side of it; and, consequently, the 
Moon's orbit only crosses the Earth's orbit in two opposite 
points, called the Moon's nodes. [For an explanation of the 
Nodes of a planet's orbit, see page 186 and cut.] 

When the Moon is in one of these points, or nearly so, at 
the time of new Moon, the Sun will be eclipsed. When she 
is in one of them, or nearly so, at the time of full Moon, the 
Moon will be eclipsed. But at all other new Moons, the 
Moon either passes above or below the Sun, as seen from 
the Earth ; and, at all other full Moons, she either passes 
above or below the Earth's shadow ; and consequently there 
can be no eclipse. 

NEW AND FULL MOONS WITHOUT ECLIPSES. 

Above the Sun. Above the Earth'* shadow. 




Below the Sun. 



Below the Earth's skadow 



In the preceding cut, one of the nodes is between the eye 
of the observer and the Earth, and the other beyond the 
Earth. Of course then the Moon would pass either above 
or below the Earth's shadow at full Moon, and either above 
or below the Sun at new Moon, so that no eclipse would be 
produced in either case. 

If the Moon be exactly in one of her nodes at the time of 
her change, the Sun will be centrally eclipsed. If she be 
U° from her node at the time of her change, the Sun will 
appear at the equator to be about 11 digits eclipsed. If 
she be 3° from her node at the time of her change, the Sun 
will be 10 digits eclipsed, and so on ; a digit being the twelfth 
part of the Sun's diameter. But when the Moon is about 
18° from her node, she will just touch the outer edge of the 
Sun, at the time of her change, without producing any 
eclipse. These are called the ecliptic limits. Between 

In what circumstances is the Sun centrally eclipsed ? What is tlie ratio between the 
Moon's distance from her node, and the number of digits that the Sun is eclipsed? 
What are these limits called ? Will there alvvavs be eclipses when the Moon is within 
these limits ? What is the ecliptic timitfor the. Sun ? What is it for the Moon I What 
number of degrees, then, ere there abmtt each node, end heno many out of S6(P, in which 
solar eclipses can happen? How many in zvhich lunar eclipses vsualty happen? 



SOLAR AND LUNAR ECLIPSES. 225 

these limits, an eclipse is doubtful, and requires a more ex- 
act calculation. 

The mean ecliptic limit for the Sun is 16^° on each side of the node, the 
mean ecliptic limit for the Moon is 10|° on each side of the node. In the former 
case, then, there are 33 degrees about each node, making, in all, 66° out of 
360°, in which eclipses of the Sun may* happen : in the latter case, there are 21° 
about each node, making, in all. 42° out of 3d0° in which eclipses of the Moon 
usually occur. The proportion of the solar to the lunar eclipses, therefore, is 
as 66 to 42, or as 11 to 7. Yet, there are more visible eclipses of the Moon! at 
any given place than of the Sun ; because a lunar eclipse is visible to a whole 
hemisphere, a solar eclipse only to a small portion of it. 

The greatest possible duration of the annular appearance 
of a solar eclipse, is 12 minutes and 24 seconds ; and the 
greatest possible time during which the Sun can be totally 
eclipsed, to any part of the world, is 7 minutes and 5S sec- 
onds. The Moon may continue totally eclipsed for one hour 
and three quarters. 

The diameter of the Sun and Moon, respectively, is divi- 
ded into twelve equal parts, called Digits, thus : 

Five Digits eclipsed. Twelve Digits. 





Here it will be observed, that a digit is not a twelfth pan 
of the surface of the Sun or Moon, but the twelfth part of 
their respective diameters. Consequently, when the con- 
cave limb of the Moon covers five digits of the Sun, as shown 
in the left hand figure, it will obscure considerably less than 
five twelfths of the Sun's surface. 

Eclipses of the Sun always begin on his western edtre. 
and end on his eastern; but all eclipses of the Moon cotri- 
mence on her eastern edge, and end on her western. 

The reason for this will be well understood By the aid of 
the accompanying figures. 



H hat then is the proportion of the, solar to the lunar eclipses? Why thm are there 
more eclipses ef tne Moon visible at any given place than of the Sun ? What i* the 
greatest possible duration of the annular appearance of a solar eclipse' What is the 
greatest passible duration oi a total solar eclipse to any part of the world i What is the 
greatest duration of a total lunar eclipse ? On which side of the Sun do solar eclipses 
u ways begin, and on which dp they end? On which side of the Moon do lunar eclipses 
always begin, and on u Inch do they end ? In what circumstances is th- Moon tor.ii'v 
eclipsed J Beyond what distance from her node, if she be, will she only touch the 
Earths shadow and not be eclipsed? On what then does the duration of lunar 
eclipses depend/ What is meant by Digits, in the description of eclipses ? Suppose 
ma digits are eclipsed, do they amount to half the dun's surface' If not why* 



226 SOLAR AND LUNAR ECLIPSES. 

Lunar Eclipse. Solar Eclipse. 




Let the student turn his face to the south, and hold tliR 
book up open before him, and he will see at once, by the 
right hand figure, that the Moon, in going eastward, must 
obscure the west or right hand side of the Sun first. In the 
figure on the left, the Moon, in revolving eastward as before, 
comes in contact with the west side of the Earth's shadow 
first, consequently her own eastern limit is first obscured. 

If the Moon, at the time of her opposition, be exactly in 
her node, she will pass through the center of the Earth's 
shadow, and be totally eclipsed. If, at the time of her oppo- 
sition, she be within 6° of her node, she will still pass through 
the Earth's shadow, though not centrally, and be totally 
eclipsed : but if she be 12° from her node, she will only just 
touch the Earth's shadow, and pass it without being eclipsed. 

The duration of lunar eclipses, therefore, depends upon the difference be- 
tween the diameter of the Moon and that section of the Earth's shadow through 
which she passes. When an eclipse of the Moon is both total and central, its 
duration is the longest possible, amounting nearly to 4 hours ; but the duration 
of all eclipses not central varies with her distance from the node. 

In what circumstances is the. duration of the lunar eclipse the. longest possible! 
Wtw.t is the length of the greatest duration of a lunar eclipse ) With tohat aoes Ui» 
duration of eclipses, not central, vary ) 



SOLAS. AND LUNAR ECLIPSES. 
ECLIPSES OF THE MOON. 



227 




The diameter o£ the Earth's shadow, at the distance 01 
Ihe Moon, is nearly three times as large as the diameter ot 
the Moon ; and the length of the Earth's shadow is nearly four 
times as great as the distance of the Moon; exceeding it in 
the same ratio that the diameter of the Earth does the dia- 
meter of the Moon, which is as 3.663 to 1. 



The length of the Earth's shadow, and its diameter Diameter Length of 
at the distance of the Moon, are subject to the varia- of the the shadow 
tions exhibited in the following table: shadow. in miles. 



Sun at the perigee 



*Jun at his mean distance 



Sun at the apogee 



Moon at the apogee 

[ Moon at her mean distance 

Moon at the perigee 

Moon at the apogee 

| Moon at her mean distance 

Moon at the perigee 

Moon at the apoiree 

| Moon at her mean distance 

Moon at the perigee 



| 5,232 

I 5,762 

! 6.292 

I 51270 

' 5.799 

! 6,329 

i 5,306 

I 5.836 

I 6.365 



The first column of figures expresses the diameter of the Earth's shadow at 
the Moon : and as the diameter of the Moon is only 2162 miles, it is evident that 
it can always be comprehended by the shadow, which is more than twice as 
broad as the disc of the Moon. 

The time which elapses between two successive changes 
of the Moon is called a Lunation, which, at a mean rate, is 
about 2% da}^s. If 12 lunar months were exactly equal t"> 
the 12 solar months, the Moon's nodes would always occupy 
the same points in the ecliptic, and all eclipses would hap- 
pen in the same months of the year, as is the case with 
the transits of Mercury and Venus: but, in 12 luna'ions, or 
lunar months, there are only 354 days; and in this time the 
Moon has passed through both her nodes, but has not quite 
accomplished her revolution around the Sun: the conse- 
quence is, that the Moon's nodes fall back in the ecliptic at 
the rate of about 19?° annually; so that the eclipses happen 
sooner every year by about 19 days. 

What is the diameter of the Earth's shadow at the distance of the Moon? What is 
the leneih of the Earth's shadow? What is their ratio to each other? Between what 
HpUtsdoes the length of the Earth's shadow, and its diameter at the distance of the 
Moon, vary ? What is the breadth of the Earth's shadoic compared with that of the disc 
iff the Mo»nl What is a lunation 1 How many days does * lunation embrace? Why da 
n<*t all eclipses happen in the same months of the ye:' How far do the .Moon's nodes 
tali baelc in the ecliptic annually, and how much 6\.c « *) the eclipses happ« »»ery 
year? 



228 SOLAR AND LUNAR ECLIPSES. 

As the Moon passes from one of her nodes to the other in 
173 days, there is just this period between two successive 
eclipses of the Sun, or of the Moon. In whatever time of 
the year, then, we have eclipses at either node, we may be 
sure" that in 173 days afterwards, we shall have eclipses at 
the other node. 

As the Moon's nodes fall back, or retrograde in the ecliptic, at the rate of 19i° 
every year, they will complete a backward revolution entirely around the 
ecliptic to the same point again, in 18 years, 225 days; in which time there 
would always be a regular period of eclipses, if any complete number of 
lunations we're finished without a remainder. But this never happens ; for if 
both the Sun and Moon should start from a line of conjunciion with either of the 
nodes in any point of the ecliptic, the Sun would perform 18 annual revolutions 
and 222^ of another, while the Moon would perform 230 lunations, and 85° of an- 
other, before the node would come around to the same point of the ecliptic 
again ; so that the Sun would then be 138° from the node, and the Moon So 3 from 
the Sun. 

But alter 223 lunations, or 13 years, 11 days,* 7 hours, 42 minutes, and 31 
seconds, the Sun, Moon, and Earth, will return so nearly in the same position 
with respect to each other, that there will he & regular return of the same eclip- 
ses/or many ages. This grand period was discovered by the Chaldeans, and 
by them called Saros. If therefore, to the mean time of any eclipse, either of 
the Sun or Moon, we add the Chaldean period of 18 years and 1 1 days, we 
shall have the return of the same eclipse. This mode of predicting eclipses 
will hold good for a thousand years. In this period there are usually 70 eclip- 
ses ; 41 of the Sun and 29 of the Moon. 

The number of eclipses in any one year, cannot be less 
than two, nor more than seven. In the former case, they 
will both be of the Sun; and in the latter, there will be five 
oi the Sim, and two of the Moon — those of the Moon will be 
total. There are sometimes six; but tne usual number is 
four: two of the Sun, and two of the Moon. 

The cause of this variety is thus accounted for. Although the Sun usually 
passes by both nodes only once in a year, he may pass the same node asjain a 
little before the end of the year. In consequence of the retrograde moiion of 
the Moon's nodes, he will come to either of them 173 days after passing the 
other. He may, therefore, return to the same node in about 346 days, having 
thus passed one node twice and the other once, making each time, at each, an 
eclipse of both the Sun and the Moon, or, six in all. And since 12 lunations, or 
354 days from the first eclipse, in the beginning of the year, leave room for 
another new Moon' before the close of the year, and since this new Moon may 
fall within the ecliptic limit, it is possible for the Sun to be eclipsed again. Tints 
there may be seven eclipses in the same year. 

r leap years in this interval, add 11 days ; but if there are Jive, add 

In what time does the Moon pass from one of her nodes to the other? What is 
the length of the time which elapses between two successise eclipses of the Sun oi 
the Moon? After there have been eclipses at one node, in what time may we !>e sure 
that there will be eclipses at the other ? In what lime do the Moon's node* cum- 
plete a backward revolution around the ecliptic! Why is there not always a regular 
period of eclipses in this time! If the Sun and Moon should both start from a lint 
of conjunction with either node, how many revolutions would the Sun perform, and 
how many lunations the Moon, before, the nods would come around to the. same point 
again 1 After how many lunations will the Sun, Moon, and Earth, return so nearly 
to the same position with, respect to each other, that there will be a regular return of 
the same eclipses for mrny acts'! What nation discovered this grand perml. and 
what did they call it'/ What is the mode of predicting eclipses, with which this faet 
furnishes us! How many eclipses are there usually in this period! What ii the 
least, and what the preatest numher of eclipses, in any one year; In the former case, 
what eclipses will they he? What, in the latter? What is the usual numher of 
eclipses in the year, and what eclipse* are they? Please explain t/ie causs of thit 
variety. 



MARS. 



229 



Again : when the Moon changes in either of her nodes, she cannot coma 
Within the lunar ecliptic limit at the next full, (though if she be full in one of her 
nodes, she may come into the solar ecliptic limit at her next change.} and six 
months afterwards, she will change near the other node ; thus making only two 
eclipses. 

The following is a list of all the solar eclipses that will be visible in Europe 
and America during the remainder of the present century. To those which 
will be visible in New England, the number of digits is annexed 



Year. 


Month 


Day and hour. 


Digits 


Year. 


Month. 


Day and hour. 


Digits. 


1851, 


July 


28 7 4S A. 


M. 


3§ 


1876, 


Mar. 


25 4 11 P. M. 


3| 


1854, 


Mav 


26 4 26 P. 


M. 


1I§ 


1878, 


July 29 4 56 P. M. 


7i 


1853, 


Mar. 


15 6 14 A. 


M. 


u 


18 r 9, 


July 


19 2 A. M. 




1859, 


July 


29 5 32 P. 


M. 


1880, 


Dec. 


31 7 30 A. M. 


5£ 


I860, 


July 


18 7 23 A. 


M. 


6 , r 


1882, 


May 


17 1 A. M. 




1861, 


Dec. 


31 7 30 A. 


M. 


4l 


1885, 


Mar. 


16 35 A. M. 




1863, 


May 


17 1 OP. 


M. 




18S6, 


Aug. 


29 6 30 A. M. 


1865, 


Oct. 


19 9 10 A. 


M. 


3| 


1837, 


Aus. 


18 10 P. M. 




1SG6, 


Oct. 


8 11 12 A. 


M. 





1690, 


June 


17 3 A. M. 




1867, 


Mar. 


6 3 A. 


M. 




1891. 


June 


6 Mer. 




1863, 


Feb. 


23 10 A. 


M. 




1892, 


Oct. 


20 19 P. M. 


8i 


•869, 


Aug. 


7 5 21 A. 


Mr. 


10 J 


1895, 


Mar. 


26 4 A. M. 




1870, 


Dee. 


2-2 6 A. 


ivr. 




1S96, 


Aug. 


9 Mer. 




1873, 


May 


26 3 A. 


M. 




1897. 


July 


29 3 8 A. M. 


4i 


1S74. 


Oct. 


10 4 A. 


M. 




1899, 


June 


8 Mer. 




1875, 


Sept. 


29 5 56 A. 


M. 


Hi 


1900. 


May 


23 8 9 A. M. 


11 



The eclipses of 1S54, 1869. 1875. and 1900. will be very large. In those of 
19.58. 1561. 1873, 1875. and 1350, the Sun tcili 'rise eclipsed. 
■ Those of 1S54 and 1375, will be annular. The scholar can continue this table, 
or extend it backwards, by adding or subtracting the Chaldean period of 13 
year*-, 11 days, 7 hours, 54 minutes, and 31 seconds. * 



MARS. 

Mars is the first of the exterior planets, its orbit lying 
iiumediately without, or beyond, that of the Earth, while 
those of Mercury and Venus are within. 

Mars appears, to the naked eye, of a fine ruddy complex- 
ion; resembling, in color, and apparent magnitude, the star 
Antares, or Aldebaran. near which it frequently passes. It 
exhibits its greatest brilliancy about th°. time that i* rises 
when the Sun sets, and sets when the S_m rises; be'- .use it 
is then nearest the Earth. It is least brilliant wher / rises 
and sets with the Sun ; for then it is five times lar.A^r re- 
moved from us than in the former case. 

Its distance from the Earth at its nearest approach is about 
50 millions of miles. Its greatest distance from us is about 
210 millions of miles. In the former case, it appears nearly 



Vhat id the position of Mars in the solar system? Describe its appearance to the 
lakedeve. When does it exhibit its cre.ite<t brilliancy Why is it most brilliant aX 
this time What are its least and greatest distances from us? How much larger dosa 
tear in the former coae than in U*e latter t 

20 



230 MAR3. 

25 times larger than m the latter. When it rises before the 
Sun, it is our morning star ; when it sets after the Sun. it is 
our evening star. 

The distance of all the planets from the Earth, whether they be interior or ex- 
terior planets, varies within the limits of the diameters of their orbits; for when 
a planet is in that point of its orbit which is nearest the Earth, it is evidently 
nearer by the whole diameter of its orbit, than when it is in the opposite point, 
on the other side of its orbit. The apparent diameter of the planet will also vary 
for the same reason, and to the same degree. 

Mars is sometimes seen in opposition to the Sun. and 
sometimes in superior conjunction with him ; sometimes 
gibbous, but never horned. In conjunction, it is never seen 
to pass over the Sun's disc, like Mercury and Venus. This 
proves not only that its orbit is exterior to the Earth's orbit, 
but that it is an opaque body, shining only by the reflection 
of the Sun. 

The motion of Mars through the constellations of the zodiac 
is but little more than half as great as that of the Earth ; it 
being generally about 57 days in passing over one sign, which 
is at the rate of a little more than half a degree each day. 
Thus, if we know what constellation Mars enters to-day. we 
may conclude that two months hence it will be in the next 
constellation ; four months hence, in the next ; six months, in 
the next, and so on. 

Mars performs his revolution around the Sun in one year 
and 10ij months, at the distance of 145 millions of miles ; mov- 
ing in its orbit at the mean rate of 55 thousand miles an hour. 
Its diurnal rotation on its axis is performed in 24 hours, 39 
minutes, and 21^ seconds; which makes its day about 44 
minutes longer than ours. 

Its mean sidereal revolution is performed in 086.9795453 solar days; or in 636 
davs. 23 hours, 30 minutes, 41.4 seconds. Its synodical revolution is performed 
in 779 936 solar days ; or in 779 days, 22 hours, 27 minutes, and 50 seconds. 

Its form is that of an oblate spheroid, whose polar diameter 
is to its equatorial, as 15 is to 16, nearly. Its diameter 
is 4222 miles. Its bulk, therefore, is 7 times less than that 
of the Earth ; and being 50 millions of miles farther from 
the Sun, it receives from him only half as much light and 
heat. 

The inclination of its axis to the plane of its orbit, is about 

Within what limits does the distance of all the planets from the Earth vary! With 
what does the apparent diameter of a planet vary! What moon-like phases has 
Mars ? What does the fact., that it never assumes the crescent form at its conjunction, 
prove, in regard to its situation ? How do we know it to be opaque ? What is the rate 
ei'its motion through the constellations of the zodiac, compared with that of the Karth 1 
How long is it in passing over one sign? At what rate per day is this? How, then, if 
we knew in what constellation it is at any one time, may we determine in what con- 
stellation it will be at any subsequent time ? In what time does it perform its revolu- 
tion around the San ? What is its distance from the Sun ? What is the mean rate of 
its motion in its orbit per hour? In what time does it perform it« revolution on ltt 
axis ? What, then, is the length of its day, compared with that of the Earth ? In what 
time doe-? it perform its mean sidereal revolntion ? In what tine, its synodical revolu- 
tion ? What are its form and dimensions ? 



MARS. 231 

28| . Consequently, its seasons must be very similar to 
those of the Earth. Indeed, the analogy between Mars and 
the Earth ^s greater than the analogy between the Earth 
and any otner planet of the solar system. Their diurnal 
motion, and of course the length of their days and nights, are 
nearly the same; the obliquity of their ecliptics, on which 
the seasons depend, are not very different ; and. of all the 
superior planets, the distance of Mars from the Sun is by far 
the nearest to that of the Earth; nor is the length of its 
year greatly different from ours, when compared with the 
years of Jupiter. Saturn, and Herschel. 

To a spectator on this planet, the Earth will appear al- 
ternately, as a morning and evening star ; and will exhibit 
all the phases of the Moon, just as Mercury and Venus do 
to us ; and sometimes like them, will appear to pass over 
the Sun's disc like a dark round spot. Our Moon will never 
appear more than a quarter of a degree from the Earth, al- 
though her distance from it is 240.000 miles. If Mars be 
attended by a satellite, it is too small to be seen by the mosJ: 
powerful telescopes. 

When it is considered that Vesta, the smallest of the asteroids, which is once 
and a half times the distance of Mars from us, and only 269 miles in diameter, 
is perceivable in the open space, and that without the presence of a more conspi- 
cuous body to point it out, we may reasonably conclude that Mai's is without a 
moon. 

The progress of Mars in the heavens, and indeed of all the superior planets, 
will, like Mercury and Venus, sometimes appear direct, sometimes retrograde, 
and sometimes he will seem stationary. Wuen a superior planet first becomes 
visible in the morning, west of the Sun. a little after its conjunction, its motion 
is direct, and also most rapid. When it is first seen east of the Sun, in the 
evening, soon after its opposition, its motion is retrograde. These retrograde 
movements and stations, as they appear to a spectatorfrom the Earth, are com- 
mon to all the planets, and demonstrate the truth of the Copernican system. 

The telescopic phenomena of Mars afford peculiar interest 
to astronomers. They behold its disc diversified with nu- 
merous irregular and variable spots, and ornamented with 
zones and belts of varying brilliancy, that form, and disap- 
pear, by turns. Zones of intense brightness are to be seen 
in its polar regions, subject, however, to gradual changes. 
That of the southern pole is much the most brilliant. Dr. 
Herschel supposes that they are produced by the reflection 
of the Sun's light, from the frozen regions, and that the melt- 
ing of these masses of polar ice is the cause of the variation 
in their magnitude and appearance. 

What, then, is its bulk, compared with the Earth's, and how much less light and heat 
does it receive tromtheSun? What is the inclination of its axis to the plane of its orbit? 
How are its seasons, compared with those of the Earth ? In what particulars is there 
a greater analogv between Mars and the Earth, than between the Earth and any other 
planet in the solar system l What must be the appearance of the Earth to a spectator 
at Mars? What is the greatest distance from the Earth at which our Moon will ap- 
p-ur to him to be? Why may we reasonably conclude that Mars has no satellite? 
Describe the progress of Mars through the heavens. What system do these retrograde 
THovements and stations, common to all the. planets as seen from the Earth, serve to 
utabtish? What are the telescopic phenomena of Mars ? 



232 MARS. 

He was the more confirmed in these opinions by observing 
that after the exposure of the luminous zone about the north 
pole to a summer of eight months, it was considerably de- 
creased, while that on tke south pole, which had been i.a 
total darkness during eight months, had considerably in- 
creased. 

He observed, farther, that when this spot was most lumi- 
nous, the disc of Mars did not appear exactly round, and 
that the bright part of its southern limb seemed to be swollen 
or arched out beyond the proper curve. 

TELESCOPIC APPEARANCES OF MARS. 




The extraordinary height and density of the atmosphere 
of Mars, are supposed to be the cause of the remarkable 
redness of its light. 

It has been found by experiment, that when a beam of 
white light passes through any colorless transparent medium, 
its color inclines to red, in proportion to the density of the 
medium, and the space through which it has traveled. Thus 
the Sun, Moon, and stars, appear of a reddish color when 
near the horizon; and every luminous object, seen through 
a mist, is of a ruddy hue. 

This phenomenon may be thus explained : — The momentum of the red, or 
least refrangible rays, being greater than that of the violet, or most refrangible 
rays, the former will make their way through the resisting medium, while the 
latter are either reflected or absorbed. The color of the beam, therefore, when 
it reaches the eve, must partake of the color of the least refrangible rays, and 
this color must increase with the distance. The dim light, therefore, by which 
Mars is illuminated, having to pass twice through its atmosphere before it reaches 
the Earth, must be deprived of a great proportion of its violet rays, and conse- 
quently then be red. Dr. Brewster supposes that the difference of color among 
the other planets, and even the fixed stars, is owing to the different heights and 
densities of their atmospheres. 

How does Dr. Herschel account for them ? How may the remarkable redness of thd 
light of Mars be accounted for? 



THE ASTEE.OIDS. 233 

THE ASTEROIDS, OR TELESCOPIC PLANETS. 

Ascending higher in the solar system, we find, between 
the orbits of Mars and Jupiter, a cluster often small planets, 
which present a variety of anomalies that distinguish them 
from all the older planets of the system. Their names are 
Vesta. Juno. Ceres, Pallas, Astrea, Hebe, Iris, Flora. Metis, 
and Hygiea. These have all been discovered during the 
present century. 

The dates of their discovery, and the names of their discoverers, are as 
follows : — 

Ceres. January 1, 1501, bv M. Piazzi, of Palermo. 
Pallas, March 23, 1802. by M. Olbers. of Bremen. 
Juno, September 1. lS04,"by M. Harding, of Bremen. 
Vesta, March 29, 1807, by M. Olbers. of Bremen. 
Astrea. December 8, 1845, bv Hencke, of Dresden. 
Hebe. July 5. 1S47. " '• " 

Iris, August 13, 1847, by Hind, of London. 
Flora, October 18th. 1847, " " 

Metis, April 25th, 1843, by Graham, of Sligo. 
Hygiea, April 12, 1849, by Gasporis, of Naples. 

The scientific Bode* entertained the opinion, that the plane- 
tary distances, above Mercury, formed a geometrical series. 
each exterior orbit being double the distance of its next in- 
terior one, from the Sun; a fact which obtains with remark- 
able exactness between Jupiter, Saturn, and Herschel. But 
this law seemed to be interrupted between Mars and Jupi- 
ter. Hence he inferred, that there was a planet wanting in 
that interval; which is now happily supplied by the discov- 
ery of the ten star-form planets, occupying the very space 
where the unexplained vacancy presented a strong objection 
to his theory. 

These bodies are much smaller in size than the older 
planets — they ail revolve at nearly the same distances from 
the Sun, and perform their revolutions in nearly the same 
periods — their orbits are much more eccentric, and have a 
much greater inclination to the ecliptic — and what is alto- 
gether singular, except in the case of comets — all cross each 
other ; so that there is even a possibility that two of these 



* According to him. the distances of the planets may be expressed nearly as follows : 


the Earth's distance from the Sun being 10. 


Mercury 4 =4 


Asteroids 4+3X2^ = 28 


Venus 4+3X1 - 7 


Jupiter 4+3X2 4 = 52 


The Earth 44-3X2 = 10 


Saturn 4+3X2 3 - 100 


Mars 4+3X2* - 16 


Herschel 4+3X2 6 => 196 



Comparing these values -with the actual mean distances of the planets from the Sui . 
we cannot hut remark the near agreement, and can scarcely hesitate to pronounce thai 
the respective distances of the planets from the Sun, were assigned according to a law, 
although we are entirely ignorant of the exact law, and of the reason for that law.— 
Brink! c/s Element 

What new planets have been discovered within the present century ? Where are they 
lituated? What are the dates of their discovert/, and the names of their discoverers* 
Why aid Bode inter that there was a planet wanting between Mars and Jupiter i 

20* 



234 THE ASTEROIDS. 

bodies may, gome time, in the course ol their revolutions, 
r-ome into collision. 

The orbit of Vesta is so eccentric, that she is sometimes 
farther from the Sun than either Ceres, Pallas, or Juno, 
although her mean distance is many millions of miles less 
than theirs. The orbit of Vesta crosses the orbits of all the 
other three, in two opposite points. 

Tke student should here refer to the Figures, Plate 1 of the Atlas, and ver- 
ify such of these particulars as are there represented. It would be well for 
the teacher to require him ro observe particularly the positions of their orbits, 
and to state their different degrees of inclination to the plane of the ecliptic. 

From these and other circumstances, many eminent as- 
tronomers are of opinion, that these ten planets are the frag- 
ments of a large celestial body which once revolved between 
Mars and Jupiter, and which burst asunder by some tremen- 
dous convulsion, or some external violence. The discovery 
of Ceres by Piazzi, on the first day of the present century, 
drew the attention of all the astronomers of the age to that 
region of the sky, and every inch of it was minutely explored. 
The consequence was. that, in the year following, Dr. Olbers, 
of Bremen, announced to the world the discovery of F alias, 
situated not many degrees from Ceres, and very mu:h re- 
sembling it in size. 

From this discovery, Dr. Olbers first conceived the idea 
that these bodies might be the fragments of a former world ; 
and if so, that other portions of it might be found either in the 
same neighborhood, or else, having diverged from the same 
point, :t they ought to have two common points of reunion, or 
two nodes in opposite regions of the heavens through which 
all the planetary fragments must sooner or later pass." 

One of these nodes he found to be in the constellation 
Virgo, and the opposite one. in the Whale ; and it is a re- 
markable coincidence that it was in the neighborhood of 
the latter constellation that Mr. Harding discovered the 
planet Juno. In order therefore to detect the remaining 
fragments, if any existed, Dr. Olbers examined, three times 
every year, all the small stars in Virgo and the Whale: 
and it was actually in the constellation Virgo, that he dis- 
covered the planet Vesta. Some astronomers think it not 
unlikely that still additional fragments of a similar descrip- 
tion may hereafter be discovered. Dr. Brewster attributes 

In what particulars do these new planets differ from the older planets? How is it 
possible that two of them should ever come into collision 7 How is it that Vesta is 
sometimes farther from ihe Sun than either Geres. Pallas, or Juno, when her n 
lance is many millions of miles less than theirs ? "What is the position of her orbit with 
regard to their orbits ? What theory in regard to the origin of these planets have sora« 
astronomers derived from these and some other circumstanres ? Who first conceived 
this idea? How came he to have this idea? Where did he imagine other frag- 
ments might be found? In what constellations did he find these nodes to be? 
Where were the planets Juno and Vesta actually found ? How did Dr. Olbers dis- 
cover Vesta ? 



THE ASTEROIDS. 235 

trie fall of meteoric stones to the smaller fragments of these 
bodies happening to come within the sphere of the Earth's 
attraction. 

Meteoric stones, or what are generally termed aerolites, are stones which 
j sometimes fall from the upper regions of the atmosphere upon the Earth. 
The substance of which they are composed, is, for the most part, metallic ; but 
the ore of which it consists is not to found in the same constituent proportions 
in any known substance upon the Earth. Their fall is generally preceded by a 
luminous appearance, a hissing noise, and a loud explosion ; and when found 
immediately after their descent, they are always hot, and usually covered with 
a black crust, indicating a state of exterior fusion. 

Their size varies from that of small fragments of inconsiderable weight, to 
that of the most ponderous masses. They have been found to weigh from 300 
pounds to several tons; and they have descended to the earth with a force 
sufficient to bury them many feet under the surface. 

Some have supposed that they are projected from volcanoes in the Moon ; 
others that they proceed from volcanoes on the Earth ; while others imagine 
that they are generated in the regions of the atmosphere ; but the truth proba- 
bly is not yet ascertained. In some instances, these stones have penetrated 
through the roots of houses, and proved destructive to the inhabitants. 

If wc carefully compute the force of gravity in the Moon, we shall find that 
if a body were projected from her surface with a momentum that would cause 
U to move at the rate of 8,200 feet in the first second of time, and in the direc- 
tion of a line joining the centers of the Earth and Moon, it would not fall again 
to the surface of the Moon ; but would become a satellite to the Earth. Such an 
impulse might, indeed, cause it, even after many revolutions, to fall to the 
Earth. The fall, therefore, of these stones, from the air, may be accounted 
for in this manner. 

Mr. Harte calculates, that even a velocity of 6000 feet in a second, would be 
sufficient to carry a body projected from the surface of the Moon beyond the 
power of her attraction. If so, a projectile force three times greater than that 
of a cannon, would carry a body from the Moon, beyond the point of equal at- 
traction, and cause it to reach the Earth. A force equal to this is often exerted 
by our volcanoes, and by subterranean steam. Hence, there is no impossibi- 
lity in the supposition of their coming from the Moon ; but yet I think the 
theory of aerial consolidation the more plausible. 

Vesta appears like a star of the 5th or 6th magnitude, 
shining with a pure steady radiance, and is the only one of 
the asteroids which can be discerned by the naked eye. 

Juno revolves around the Sun in 4 years, 4i months, at 
the mean distance of 254 millions of miles, moving in her 
orbit at the rate of 41 thousand miles an hour. Her diame- 
ter is estimated at 1393 miles. This would make her mag- 
nitude 183 times less than the Earth's. The light and heat 
which she receives from the Sun, is seven times less than 
that received by the Earth. 

The eccentricity of her orbit is so great, that her greatest 
distance from the Sun is nearly double her least distance; 

To what does Dr. Brewster attribute the fall of meteoric stones? What ismeant by 
the expression, meteoric stones? Of what substance are they composed'! In what re- 
spect do the.y differ from any metallic substances knoion on the Earth) What indica- 
tions generally precede their fall i In what state are they found to be after their de- 
scent"! What is their magnitude! What theories have been adopted to account for 
their origin? Explain hoiv it is not impossible that they may come from the Moon. 
Describe the appearance of Vesta. 

What is the planet next in order after Vesta? In what time does she complete her 
revolution around the Sun ? What is her mean distance from him > What the raie of het 
motion per hour ? What is the length of her diameter? How much less, then is net 
magnitude, than that of the Earth? How much ligfatand heat does she receive from 
the Sun, compared with those received by the Earth ? How much greater is her great- 
est distance from the Sun, than her least distance} 



236 THE ASTEROIDS. 

so that, when she is in her perihelion, she is nearer the Sun 
by 130 millions of miles, than when she is in her aphdicn. 
This great eccentricity has a corresponding effect upon her 
rate of motion ; for being so much nearer, and therefore so 
much more powerfully attracted by the Sun at one time 
than at another, she moves through that half of her orbit 
which is nearest the Sun, in one half of the time that she 
occupies in completing the other half. 

According to Schroeter, the diameter of Juno is 1425 miles ; and she is sur- 
rounded by an atmosphere more dense than that of any of the other planets. 
Schroeter also remark's, that the variation in her brilliancy is chiefly owing to 
certain changes in the density of her atmosphere ; at the same time he thinks 
it not improbable that these changes may arise from a diurnal revolution on 
her axis. 

Ceres revolves about the Sun in 4 years, 7£ months, at 
the mean distance of 263i millions of miles, moving in her 
orbit at the rate of 41 thousand miles an hour. Her diame- 
ter is estimated at 1582 miles, which makes her magnitude 
125 times less than the Earth's. The intensity of the light 
and heat which she receives from the Sun, is about 71 times 
less than that of those received by the Earth. 

Ceres shines with a ruddy color, and appears to be only 
about the size of a star of the eighth magnitude. Conse- 
quently she is never seen by the naked eye. She is sur- 
rounded by a species of cloudy or nebulous light, which gives 
her somewhat the appearance of a comet, forming, according 
to Schroeter, an atmosphere 675 miles in height. 

Ceres, as has heen said, was the first discovered of the asteriods. At her dis- 
covery, astronomers congratulated themselves upon the harmony of the sys- 
tem being restored. They had long wanted a planet to fill up the great void be- 
tween Mars and Jupiter, in order to make the system complete in their own 
eyes; but the successive discoveries of Pallas and Juno again introduced con- 
fusion, and presented a difficulty which they were unable" to solve, till Dr. Ol- 
bers suggested the idea that these small anomalous bodies were merely the 
fragments of a larger planet, which had been exploded by some mighty convul- 
sion. Among the most able and decided advocates of this hypothesis, is Dr. 
Brewster, of Edinburgh. 

Pallas performs her revolution around the Sun in 4 years, 
7f months, at the mean distance of 264 millions of miles, 
moving in her orbit at the rate of 41 thousand miles an hour. 



How much less time does she occupy in moving through that half of her orbit nearest 
to the Sun, than in moving through that which is farthest from him ? What is her dia- 
meter according to Schroeter} According to the same astronomer what is the density of 
her atmosphere, compared with that of the other planets ? To wjiat does he attrib ute the 
variation in her brilliancy ? What is the next planet in order after Juno ? In what time 
does she complete her revolution about the Sun ? What is her mean distance from him ? 
What is the rate of her motion per hour! What is her diameter ? How great is her 
magnitude, compared with that of the Earth? What is the intensity of the light and 
heat which she receives from the Sun, compared with that of those received by the 
l.arth ? Describe her appearance. 

How high, according to Schroeter, is the atmosphere formed by this nebulous light? 
/Vhy did astronomers congratulate themselves on the discovery of this planet J What 
again introduced confusion and difficulty into their system 7 How were they at length 
enabled to solve the difficulty ? "\\ hat planet is the next in order after Ceres ? In what 
time does she complete her revolution around the Sun? What is her mean distance 
from him? What is the rate of hei motion in her orbit per hour? Whatis her diameter' 



JUPITER. 237 

Her diameter is estimated at 2025 miles, which is but little 
less than that of our Moon. It is a singular and very re- 
markable phenomenon in the solar system, that two planets. 
(Ceres and Pallas.) nearly of the same size, should be situa- 
ted at equal distances from the Sun, revolve about him in 
the same period, and in orbits that intersect each other. The 
difference in the respective distances of Ceres and Pallas is 
less than a million of miles. The difference in their sidereal 
revolutions, according to some astronomers, is but a single 
day ! 

The following table exhibits the order of the Asteroids, 
beginning at the Sun; the inclination of their orbits to the 
plane of the ecliptic and their periodic time : 





Names. 


Inclination.* 


Ys. 


Days 


1. 


Flora, 


5° 52' 


55" 


3 


98 


2. 


Vesta, 


7 08 


30 


3 


230 


3. 


Iris, 


5 28 


10 


3 


250 


4. 


Metis, 


5 25 


34 


3 


251 


5. 


Hebe, 


14 44 


25 


3 


280 


6. 


Astrea, 


5 19 


17 


4 


50 


7. 


Juno, 


13 02 


39 


4 


134 


8. 


Ceres, 


10 37 


13 


4 


220 


9. 
10. 


Pallas, 
Hygiea, 


34 37 

not determined 


31 


4 


225 



The calculation of the latitude and longitude of the asteroids is a labor ol e*- 
ffeme difficulty, requiring more than 400 equations to reduce their anomalous 
perturbations to the true place. This arises from the want of auxiliary tables, 
and from the fact that the elements of the star-form planets, are very imper- 
fectly determined. Whether any of the asteroids has a rotation on its axis, 
remains to be ascertained. 



JUPITER. 



Jupiter is the largest of all the planets belonging to the 
solar system. It may be readily distinguished from the fixed 
stars, by its peculiar splendor and magnitude ; appearing to 
.the naked eye almost as resplendent as Venus, although i 
is more than seven times her distance from the Sun. 

When his right ascension is less than that of the Sun, he 
is our morning star, and appears in the eastern hemisphere 

* See representation, Plate 1 of Atlas. 

How crreat is it compared with the diameter of the Moon 3 What is the differente 
between the respective distances of Ceres and Pallas from the Sun 3 What is the dif- 
ference between the times of their sidereal revolutions 3 Why is the calcination of the 
latitude, and longitude of the asteroids a labor of extreme difficulty ? Hav any of the 
asteroids rotations on their axes i Which is the largest planet of the solar 
How may Jupiter be readily distinguished from the fixed stare? How much litrther 
S he from the Sun than Venus 3 In what case is he our morning §ta- 3 



238 JUPITER. 

before trie Sun rises; when greater, he is our evening star, 
and lingers in the western hemisphere after the Sun sets. 

Nothing can be easier than to trace Jupiter among the 
constellations of the zodiac; for in whatever constellation 
he is seen to-day, one year hence he will be seen equally 
advanced in the next constellation ; two years hence, in the 
next; three years hence, in the next, and so on ; being just 
a year, at a mean rate, in passing over one constellation. 

The exact mean motion of Jupiter in its orbit, is about one-twelfth of a degree 
in a day ; which amounts to only 30° 20' 32" in a year. 

For 12 years to come, he will, at a mean. rate, pass through 
the constellations of the zodiac, as follows : 



1854, Sagittarius. 1838, .Aries. 

1355, Capricornus, ! 359, Taurus. 

1856, Aquarius. 1860, Gemini. 

1857, Pisces. 1861, Cancer 



1850, Leo, 

1851, Virgo. 
1832, Libra. 
1853, Scorpio. 

Jupiter is the next planet in the solar system above the 
asteroids, and performs his annual revolution around the 
Sun in nearly 12 of our years, at the mean distance of 495 
millions of miles ; moving in his orbit at the rate of 30,000 
miles an hour. 

The exact period of Jupiter's sidereal revolution is 11 years, 10 months. 17 
days. 14 hours, 21 minutes. 25J seconds. His exact mean distance from the Sun 
is 495,533837 miles ; consequently, the exact rate of his motion in his orbit, ii 
29.913 miles per hour. 

He revolves on an axis, which is perpendicular to the 
plane of his orbit, in 9 hours, 55 minutes, and 50 seconds; 
so that his year contains 10,471 days and nights; each about 
5 hours long. 

His form is that of an oblate spheroid, whose polar diame- 
ter is to its equatorial, as 13 to 14. He is therefore consid- 
erably more flattened at the poles, than any of the other 
planets, except Saturn. This is caused by his rapid rotation 
on his axis; for it is a universal law that the equatorial 
parts of every body, revolving on an axis, will be swollen 
out, in proportion to the density of the body, and the rapidity 
of its motion. 

The difference between the polar and equatorial diameters of Jupiter, exceeds 
6000 miles. The difference between the polar and equatorial diameters of th« 
Earth, is only 26 miles. Jupiter, even on the most careless view through a 
good telescope, appears to be oval ; the longer diameter being parallel to Um 
direction of his belts, which are also parallel to the ecliptic. 

In what our evening? How may he be traced among the constellations of the zo- 
diac? In whst constellation will he be, each year, tor twelve years to come? What is 
his position in the solar system ? "What is his mean distance from the Sun? What is 
the rate per hour of his motion in his orbit ? What is the exact period of his sidereal 
revolution ? What is his exact mean distance from the Sttn ? What the exact rate 
per hour of his motion in his orbit ? What is the position of his axis with respect to 
the plane of his orbit? How many days and nights does his year contain ? How lonr 
tire they each ? What is his form ? What is the ratio between his polar and equatorial 
diameters ! What is the cau.-e of his being more flattened at the poles than any of 
the other planets ? What is the difference between his polar and equatorial diameter*! 
What does his form appear to be, through a good telescope 1 What is the directum of 
his longer diameter 7 



JUPITER. 239 

By this rapid whirl on its axis, his equatorial inhabitants 
arc carried around at the rate of 26.554 miles an hour ; 
which is 1600 miles farther than the equatorial inhabitants 
of the Earth are carried, by its diurnal motion, in twenty-four 
hours. 

The true mean diameter of Jupiter is 86,255 miles; which 
is nearly 11 times greater than the Earth's. His volume is 
therefore about thirteen hundred miles larger than that of 
the Earth. (For magnitude as compared with that of the 
Earthy see Plate I.) On account of his great distance from 
the Sun, the degree of light and heat which he receives 
from it, is 27 times less than that received by the Earth. 

When Jupiter is in conjunction, he rises, sets, and comes to the meridian 
with the Sun ; but is never observed to make a transit, or p^ss over the Sun's 
disc; when in opposition, he rises when the Sun sets, sets when the Sun rises, 
and comes to the meridian at midnight, which never happens in the case of an 
interior planet. This proves that Jupiter revolves in an orbit which is exterior 
to that of the Earth. 

As the variety in the seasons of a planet, and in the length 
of its days and nights, depends upon the inclination of its axis 
to the plane of its orbit, and as the axis of Jupiter has no 
inclination, there can be no difference in his seasons, on the 
same parallels of latitude, nor any variation in the length of 
his days and nights. It is not to be understood, however, 
that one uniform season prevails from his equator to his 
poles ; but that the same parallels of latitude on each side 
of his equator, uniformly enjoy the same season, whatever 
season it may be. 

About his equatorial regions there is perpetual summer; 
and at his poles everlasting winter; but yet equal day and 
equal night at each. This arrangement seems to have been 
kindly ordered by the beneficent Creator; for had his axis 
been inclined to his orbit, like that of the Earth, his polar 
winters would have been alternately a dreadful night of six 
years darkness. 

Jupiter when viewed through a telescope, appears to be 
surrounded by a number of luminous zones, usually termed 
bells, that frequently extend quite around him. These belts 
are parallel not only to each other, but, in general, to his 
equator, which is also nearly parallel to the ecliptic. They 
are subject, however, to considerable variation, both in 

At what rate per hour are his equatorial inhabitants carried by his motion on hi* Bxisl 
How much further is this than the equatorial inhabitants of the Earth are carried in n 
hour*? What is Jupiter's true mean diameter' How much croater i* it than tlia 
Earth's? What is his volume, compared with the Earth's? What is the degree of 
light and heat which he receives from the Sun, compared with that received by the 
Earth I How do ice know that Jupiter's orbit is exterior to that of the Ka> th ! What 
is the arrangement of Jupiter's seasons, and of his days and nights? Had his .wis 
been inclined to the plane of his orbit, like that of our Earth, how long would his polar 
tffbta have been 3 Describe Jupiter's appearance, ai seen thruugn i telescope. What 
1; arppored to be the cause of these phenomena 



240 JUPITER, 

breadth and number. Sometimes eight have been seen at 
©nee ; sometimes only one, but more usually three. Dr. 
Herschel once perceived his whole disc covered with small 
belts, though they are more usually confined to within 30° 
of his equator, that is, to a zone 60° in width. 

TELESCOPIC APPEARANCE3 OF JUPITER. 




Sometimes these belts continue for months at a time with 
tittle or no variation, and sometimes a new belt has been seen 
U) form in a few hours. Sometimes they are interrupted in 
their length ; and at other times, they appear to spread in 
width, and run into each other, until their breadth exceeds 
§,000 miles. 

Bright and dark spots are also frequently to be seen in 
the belts, which usually disappear with the belt3 themselves, 
though not always, for Cassini observed that one occupied 
the same position more than 40 years. Of the cause of these 
variable appearances, but little is known. They are gene- 
rally supposed to be nothing more than atmospherical phe- 
nomena, resulting from, or combined with, the rapid motion 
of the planet upon its axis. 

Different opinions have been entertainer! by astronomers respecting the cause 
of these belts and spots. By some they have been regarded as clouds, or as 
openings in the atmosphere of the planet, while others imagine that they are of 
a more permanent nature, and are the marks of great physical revolutions, 
which are perpetually agitating and changing the surface of the planet. The 
first of these opinions sufficiently explains the variations in the form and magni- 
tude of the spots, and the parallelism of the belts. The spot first observed by 
Cassini, in 1665, which has both disappeared and re-appeared in the same form 
and position for the space of 43 years, could not possibly be occasioned by any 
atmospherical variations, but seems evidently to be connected with the surface 
af the planet. The form of the belt, according to some astronomers, maybe 
accounted for by supposing that the atmosphere reflects more light than the 
body of the planet, and that the clouds which float in it, being thrown into par- 
allel strata by the rapidity of its diurnal motion, form regular instersticee, 
through which are seen its opaque body, or any of the permanent spots which 
nay come within the range of the opening. 

Relate some of the different opinions entertained by astronomers on this subject, 
dtow many sateJJites has Jupiter? How often are they visible to him? What is th* 
^stance from him of hi* first o~ "earest satellite ? What is the time of its tevolotiont 



JUPITK. 24 I 

Jupiter is also attended by four satellites or moons, some 
of which are visible to him every hour of the night; exhibit- 
insr, on a small scale and in short periods, most of the phe- 
nomena of the solar system. When viewed through a tele- 
scope, these satellites present a most interesting and beauti- 
ful appearance. The first satellite, or that nearest the pla- 
net, is 259,000 miles distant from its center, and revolves 
round it in 42? hours; and appears, at the surface of Jupi- 
ter, four times larger than our Moon does to us. His second 
satellite, being both smaller and farther distant, appears 
about the size of ours ; the third, somewhat less ; and the 
fourth, which is more than a million of miles from him, and 
takes 161 days to revolve around him, appears only about 
one third the diameter of our Moon. 

These satellites suffer frequent eclipses from passing 
through Jupiter's shadow, in the same manner as our Moon 
is eclipsed in passing through the Earth's shadow. The 
three nearest satellites fall into his shadow, and are eclipsed 
in every revolution; but the orbit of the fourth is so much 
inclined, that, it passes by its opposition to him, two years in 
six. without falling into his shadow. By means of these 
eclipses, astronomers have not only discovered that light is 
8 minutes and 13 seconds in coming to us from the Sun. but 
are also enabled to determine the longitude of places on th*i 
Earth with greater facility and exactness than by any other 
methods yet known. 

It was long since found, by the most careful observations, that when the Earn- 
' is in that part of her orbit which is nearest to Jupiter, the eclipses appear :. 
happen 8' 13'' sooner than the tables predict ; and when in that part of her or- 
bit which is farthest from him, 8' 13" later than the tables predict ; makinz a 
total difference in time, of 16' 26". From the mean of 6000 eclipses observed 
by Delambre, this disagreement between observation and calculation, was sa- 
tisfactorily settled at S' 13", while both were considered equally correct. Now 
when the'eclipses happen sooner than the tables. Jupiter is at his nearest ap- 
proach to the Earth — when later, at his greatest distance; so that the differ? nee 
in his distances from the Earth, in the two cases, is the whole diametsr of the 
Earth's orbit, or about 190 millions of miles. Hence, it is concluded that Hght 
is not instantaneous, but that it occupies 16' 26" in passing across the Earth's 
orbit, or 8' 13" in coming from the Sun to the Earth; being nearly 12 millions 
of miles a minute. 

The revolutions of the satellites about Jupiter are pre- 
cisely similar to the revolutions of the planets about Use 
Sun. In this respect they are an epitome of the solar sys- 
tem, exhibiting, on a smaller scale, the various changes tiia: 
take place among the planetary worlds. 

What is its apparent magnitude at the surface of Jupiter, oompared with the magnitui 
of the Moon, us seen by us ? What are the apparent magnitudes ef his other satellites 
M seen at his surface, compared with that of the Moon as seen at the Earth ? What 
the distance of his fourth satellite from him J What is the time of its revolution ' kkm 
often are his three nearest satellites eclipsed? How often his fourth? Wbj - 
eclipsed as often as the others? What important purposes have these eclipsed serve. 
to astronomers? State the method by ichich tfie prugressivr. tnotivn nf iishi, a«u Iks 
time which it occupies in corning to us fytnn the San, icere chssoverei. 

•21 



242 SATURN. 

Jupiter, when seen from his nearest, satellite, appears a 
thousand times larger than our Moon does to us, exhibiting 
on a scale of inconceivable magnificence, the varying forms 
of a crescent, a half moon, a gibbous phase, and a full moon, 
every 42 hours. 

The apparent diameters of Jupiter's satellites, their mean distances from him, 
aud their periodical revolutions, are exhibited in the following table. 



Satellites. 


Revolution. 


App. 

D.am. 


Mean Distance. 


First, Id. ISh. 28m. 
Second, 3 13 14 
Third, 7 3 43 
Fourth, 16 16 32 


1. 667 
1. 189 
I. 050 

0. 550 


259.000 
414,000 
647.000 
1,164000 



In passing across the disc of Jupiter, one of his satellites 
has been known to lose all its light, as if undergoing eclipse, 
until it finally became a black spot on the disc of the planet: 
after passing off the disc it resumed its light. — Prof. Mitchel. 



SATURN. 

Saturn is situated between the orbits of Jupiter and Her- 
echel, and is distinctly visible to the naked eye. It may be 
easily distinguished from the fixed stars by its pale, feeble, 
and steady light. It resembles the star Fomalhaut, both in 
color and size, differing from it only in the steadiness and 
uniformity of its light. 

From the slowness of its motion in its orbit, the pupiL 
throughout the period of his whole life, may trace «its appa- 
rent course among the stars, without any danger of mistake- 
Having once found when it enters a particular constellation, 
he may easily remember where he is to look for it in any 
subsequent year ; because, at a mean rate, it is just 2i years 
in passing over a single sign or constellation. 

Saturn's mean daily motion among the stars is only about 
2', the thirtieth part of a degree. 

Saturn entered the constellation Virgo about the beginn'm? of 1833. and con- 
tinued la it until ihe middle of the year 1835, when he passed into Libra. Ha 
continued in that constellation until 1S3S; and soon, occupying about 2| yen*! 
in each constellation, or nearly 30 years in one revolution. At this dat»,": 1349) 
he is in the constellation Pisces. 

In what respect are Jupiter's satellites an epitome of the solar system ? What is Ju- 
pitei's appearance, as seen from his nearest satellite ? What are the diameter*, mean 
distances, and lime* of the revolution of his satellites'* Where, in the solar system, it 
Saturn situated? How may it be distinguished from the fixed Htars ? What star <loe9 
it resemble? In what respects is it like it. and in what is it different from it ' How 
may his place among the stars be readily found ? What is about the rate of his mean 
daily motion among the stars? When, did Saturn enter the constellation Virgo, and 
how long did he continue in it? What constellation did he enter next, and how long 
did he continue, in it 7 Where is he at this dale 7 



243 



The mean distance of Saturn from the San is nearly dou- 
ble that oC Jupiter, being about 909 millions of miles. His 
diameter is about 82,000 miles ; his volume therefore is 
eleven hundred times greater than the Earth's. Moving in 
his orbit at the rate of 22,000 miles an hour, he requires 29£ 
years to complete his circuit around the Sun: but his diur- 
nal rotation on his axis is accomplished in 10i hours. His 
year, therefore, is nearly thirty times as long as ours, while 
pis day is shorter by more than one half. His year contains 
about 25,150 of its own days, which are equal to 10,759 of 
our days. 

The surface of Saturn, like that of Jupiter, is diversified 
with belts and dark spots. Dr. Herschel sometimes per- 
ceived five belts on his surface ; three of which were dark, 
and two bright. The dark belts have a yellowish tinge, and 
generally cover a broader zone of the planet than those of 
Jupiter. 

To the inhabitants of Saturn, the Sun appears 90 times 
less than he appears to the Earth ; and they receive from 
him only one ninetieth jjart as much light and heat. But 
it is computed that even the ninetieth part of the Sun's light 
exceeds the illuminaiing power of 3,000 full moons, which 
would be abundantly sufficient for all the purposes of life. 



TELESCOPIC VIEW OF 




The telescopic appearance ui .biuum i* uiiparwUcicu. u 
is even more interesting than Jupiter, with all his moons ;u d 

Horv long time does he occupy in passing- throuz-h each constellation, and to hat is 'he 
length of his year! What is his distance from the Sun ! How much greater is this 
than Jupiter's distance ? What is his diameter? How much creater is his volume than 
that of the Earth » What is the rate per hour ofhia motion in his o'bit? In what lime 
is his diurnal motion on his axis performed ! How many ot his own days <loe< his yeai 
wiiiiam, and bow many of ours > What is the appearance of his surface to us ' How 
rnunv belts did I>r. Herschel peceive on hi* surface ? Describe them. How much less 
toe* the Sun appear to the inhabitants of Saturn than to :is ? What decree of lisrhtarul 
heat does he receive, trim the Sun. eompa ed with that received by the Earth ' To the 
baht of how many full moons is this decree of light enual - ; Describe the telescopic 
appearance of datum. 



244 SATURN. 

belts. That which eminently distinguishes this planet from 
every other in the system, is a magnificent zone or ring, 
encircling it with perpetual light. 

The light of the ring is more brilliant than the planet 
itself. It turns around its center of motion in the same time 
that Saturn turns on its axis. When viewed with a good 
telescope, it is usually found to consist of two concentric 
rings, divided by a dark band. 

It has been ascertained, however, that these rings are 
again subdivided; the third division was distinctly seen by 
Prof. Encke, on the 25th of April, 1837, and also by Mr. 
Lassell, on the 7th of September, 1843. at his observatory 
near Liverpool, England. Six different rings were seen at 
Rome, in Italy, on the night of the 29th of May, 1838. 



SATURN IN HIS ORIIT. 




The above is a representation of Saturn in his orbit, as he 
would appear to one at a distance from the solar system, 
who could take in his whole orbit at one view, and watch 
him through his entire revolution. A and E, are the equi- 
noctial, and C and G, the solstitial points. At the former, 
the Sun shines edgewise upon and crosses the rings; so that 
tliey are nearly or quite invisible. At C and G, the planet 
is most favorably situated for observing his rings from the 
Earth. From C around to E, the Sun shines upon the south 
side. of the rings, and from E to C again upon the north 
side. The Earth is seen in her proper place much nearer 
the Sun. 

By the laws of mechanics, it is impossible that the body of the rings should 
retain its position by the adhesion of the particles alone; it must necessarily re- 
volve with a velocity that will generate centrifugal force sufficient to balance the 
attraction of Saturn. Observation confirms the truth of these principles, show- 
inn that the rings rotate about the planet in 10| hours, which is considerably 
less than the time a satellite would take to revolve about it at the samedisfance. 
Their plane is inclined to the ecliptic in an angle of 31°. In conseqence of this ob» 



SATURN. 245 

liquify of position, they always appear ol' ; otical to us, but with an eccentricity so 
, variable as to appear, occasionally, like a sv* *«ght line drawn across the planet ; in 
which case they are visible only by the aid ofsu^rior instruments. Such was their 
position in April, 1833; for the Sun was then passing from their south to their 
north side. The rings intersect the ecliptic in two opposite points, which may 
be called their nodes. These points are in longitude 170°, and 350 degrees. 
When, therefore, Saturn is in either of these points, Iris rings will be invisible 
to us. On the contrary, when his longitude is SO , or 200°. the rings may be 
seen to the greatest advantage. As the edge of the rings will present themselves 
to the Suu twice in each revolution of the planet, it is obvious that the compear- 
ance of them will occur once in about 15 years; subject, however, to the v?-i- 
ation dependent on the position of the Earth at that time. 

But it must also be obvious that to an observer upon the 
Earth, the rings would present a great variety of aspects, 
during the thirty years of the planet's revolution ; this is ac- 
tually the case. The following cut will illustrate the ap- 
pearances of the rings, at different times during the thirty 
years of his periodic revolution. 

TELESCOPIC PHASES OF SATURN 



The distance between Saturn and his inner ring, is only 
21,000 miles; being less than a tenth part of the distance of 
our Moon from the Earth. The breadth of the dark band, 
or the interval between the rings, is hardly 3,000 miles. 
The breadth of the inner ring is 20,000 miles. Being only 
about the same distance from Saturn, it will present to his 
inhabitants a luminous zone, arching the w T hoIe concave 
vault from one hemisphere to the other with a broad girdle 
of light. 

The most obvious use of this double ring is, to reflect 
light upon the planet in the absence of the Sun; what other 
purposes it may be intended to subserve, is to us unknown. 
The Sun. as has been shown, illuminates one side of it during 
15 years, or one half of the period of the planet's revolution ; 

What is the longitude of these nodes" 1 - In what position rf Saturn, then, trill tie 
tings be invisible to us. and in what position will they be seen to the best advantage/ 
Hotc often 10W the disappearance, of tlie rings occur i Explain this. In what signs 
will the planet he when the Sun shines on the south side of the rings, and in wha: in 
the norrhsidei What is the distance between Saturn and his inner ring\> How great 
is ihi>. compared with the distance of our Moon from the Earth ! What is the di.-tatice 
n the two rings' What is the breadth of the inner ring? What must be its ai 
at Saturn' What is tin- most obvious use of this double rinjr .' Ho\t lo-.g a 
lime does the Sun ei'lijh'en e o-li side of it alte natcly ' How of en and in what cii- 
•unutancej is neither side enligfrened ,-uid the ring, of coutue, invisible J 

21* 



246 SATURN. 

and, during the next 15 years, the other side is enlightened 
in its turn. 

I Twice in the course of 30 years, there is a short interval 
of time when neither side is enlightened, and when, of course 
it ceases to be visible; namely, at the time when the Sun 
reases to shine on one side, and is about to shine on the 
other. It revolves around its axis, and consequently, around 
Saturn, in 10£ hours, which is at the rate of a thousand 
miles in a minute, or 58 times swifter than the revolution of 
the Earth's equator. 

When viewed from the middle zone of the planet, in the 
absence of the Sun, the rings will appear like vast luminous 
arches, extending along the canopy of heaven, from the 
eastern to the western horizon, exceeding in breadth a hun- 
dred times the apparent diameter of our Moon. 

Besides the rings, Saturn is attended by eight satellites, 
which revolve about him at different periods and distances, 
and reciprocally reflect the Sun's rays on each other and 
on the planet. The rings and moons illuminate the nights 
of Saturn ; the moons and Saturn enlighten the rings, and 
the planet and rings reflect the Sun's beams on the satellites. 

The fourth of these satellites (in the order of their distance) was first dis- 
covered by Huygens, on the 25th of March, 1655, and in honor of the discov- 
erer, was called the Huigenian Satellite. This satellite being the lamest of all, 
is seen without much difficulty. Cassini discovered the 1st, L'd, 3d. and 5th 
satellites, between October, 16/1, and March, 1684. Br. Herschel discovered 
the 6th and 7th in 1789. These are nearer to Saturn than any of the rest, 
though, to avoid confusion, they are named in the order of their discovery. 

The sixth and seventh are the smallest of the whole ; the 
first and second are the next smallest; the third is greater 
than the first and second ; the fourth is the largest of them 
all ; and the fifth surpasses the rest in brightness. 

Their respective distances from their primary, vary from 
half the distance of our Moon, to two millions of miles. 
Their periodic revolutions vary from 1 day to 79 days. The 
orbits of the six inner satellites, that is, the 1st, 2d, 3d. 4th, 
6th, and 7th, all lie in the plane of Saturn's rings, and revolve 
around their outer edge; while the 5th satellite deviates so 
far from the plane of the rings, as sometimes to b< 
through the opening between them and the planet. Of the 
Sth satellite recently discovered, we have as yet much less 
knowledge than of its predecessors. 

In what time does the ring complete its revolution on iU axis, and, of course, around 
the planet? What is the rate per minute of its motion? How rapid is this, compared 
with the motion of the Earth's equator ' What would be the appearance of the rinjjs, 
if viewed from the middle zone of the planet, in the absence of the Sun ' How many 
moons has Saturn? How are Saturn, his rings and satellites, severally, cnlightenedl 
What are the. dates of their discovery, and the names of their discoverers ? What are 
their comparative magnitude-;, distances, and times of revolution ? What is tl 
tion of their orbits with respect to the mips of Saturn ? What dors Laplace imagine 
retains the orbits of Saturn's first six saietli:es in the plane of his equator ? 



SATURN. 247 

Laplace imagines that the accumulation of matter at Saturn's equator retains 
the orbits of the first six satellites in the plane of the equator, in the same 
manner as it retains the rinss in that plane. It has been satisfactorily ascer- 
tained, that Saturn has a greater accumulation of matter about his equator, 
and consequently that he is more flattened at the poles, than Jupiter, though 
the velocity of the equatorial parts of the former is much less than that of the 
latter. This is sufficiently accounted for by the fact, that the rings of Saturn 
lie in the plane of his equator, and act more powerfully upon those parts of his 
surface than upon any other; and thus, while they aid in diminishing the gravity 
of these parts, also aid the centrifugal force in flattening the poles of the planet. 
Indeed, had Saturn never revolved upon his axis, the action of the rings would, 
of itself, have been sufficient to give him the form of an oblate spheroid. 

The theory of the satellites of Saturn is less perfect than 
that of the satellites of Jupiter. The difficulty of observing 
their eclipses, and of measuring their elongations from their 
primary, have prevented astronomers from determining, 
with their usual precision, their mean distances and revolu- 
tions. 

We may remark, with the Christian Philosopher, that 
there is no planet in the solar system, whose firmament pre 
sents such a variety of splendid and magnificent objects as 
that of Saturn. 

The various aspects of the seven moons, one rising above 
the horizon, while another is setting, and a third approach- 
ing to the meridian ; one entering into an eclipse, and ano- 
ther emerging from one ; one appearing as a crescent, and 
another with a gibbous phase ; and sometimes the whole of 
them shining in the same hemisphere, in one bright assem- 
blage ! The majestic motion of the rings — at one time illu- 
minating the sky with their splendor, and eclipsing the stars ; 
at another, casting a deep shade over certain regions of the 
planet, and unveiling to view the wonders of the starry fir- 
mament, are scenes worthy of the majesty of the Divine 
Being to unfold, and of rational creatures to contemplate. 

Such displays of Wisdom and Omnipotence, lead us to 
conclude that the numerous splendid objects connected with 
this planet, were not created merely to shed their lustre on 
naked rocks and barren sands ; but that an immense popu- 
lation of intelligent beings is placed in those regions, to enjoy 
the bounty, and adore the goodness, of their great Creator. 

The following table exhibits the apparent and mean distances of the satellites 
from their primary (the Sth excepted), and the times of their periodical revolu- 
tion. Their distances in miles were computed from their observed micrometer 
distances; the diameter of Saturn's equator being considered equal to S0.000 



Why are astronomers less acquainted with the mean distances and revolutions of Sa- 
turn's satellites, than with those of Jupiter ? Describe the firmament of Saturn, as illu- 
minated by his rings and satellites. 



248 



HERSCHEL. 



Satellites. 




Periodic 


Distance in 


Distance in 




revolution. 


diameter. 


miles. 


1 


Od. 


22u. 38m. 


1.540 


123,2QCI 


2 


1 


8 53 


1.976 


I58.05U 


3 


1 


21 18 


2.447 


195.720 


4 


2 


17 45 


3 134 


250.720 


5 


4 


12 25 


4377 


350.160 


6 


15 


23 41 


10.143 


811.400 


7 


79 


7 55 


29.577 


2.366,160 



HERSCHEL OR URANUS. 

Herschel is the next planet in order from the Srn, beyond 
or above Saturn. To the naked eye, it appears like a star 
of only the 6th or 7th magnitude, and of a pale, bluish white; 
but it can seldom be seen, except in a very fine, clear night, 
and in the absence of the Moon. 

As it moves over but one degree of its orbit in 85 days, it 
will be seven years in passing over one sign or constellation. 

When first seen by Dr. Herschel, in 17S1, it was in the 
foot of Gemini ; so that it has not yet completed one revolu- 
tion since it ivas first discovered to be a planet. 

It is remarkable that this borlf was observed as far back as 1690. It was ?een 
three times by Flamstead, onca by Bradley, once by Mayer, and eleven times 
by Lemonnier, who registered it among the stars ; but not one of them suspected 
it to be a planet. 

The inequalities in the motions of Jupiter and Saturn, 
which could not be accounted for from the mutual attrac- 
tions of these planets, led astronomers to suppose that there 
existed another planet beyond the orbit of Saturn, by whose 
action these irregularities were produced. This conjecture 
was confirmed March 13th, 1781; when Dr. Herschel dis- 
covered the motions of this body, and thus proved it to be a 
planet. 

Herschel is attended by six moons or satellites, which re- 
volve about him in different periods, and at various distances. 
Four of them were discovered by Dr. Herschel, and two by 
his sister, Miss Caroline Herschel. It is possible that others 
remain yet to be discovered. 



What is the relative distance of the planet Herschel from the Sun ? "What is its 
appearance to the naked eye 7 In what circumstances can it be seen? What is ihe 
rate of its motion in its orbit? What is its present position? What was its 
when first discovered to be a planet? How much. then, of its revolution has been com- 
pleted, since it wa< first discovered ? At how car y a dare was this body olserxea in ft. 
heavens) Who observed it, before it was discovered to be a -planet J Horn »,, 
was it seen by them, respectively? What did they consider it to be ? What led a«ir.>- 
nomers to suppose that there existed another planet beyond Saturn? When and by 
whom was Herschel discovered to be j>. planet .' How many moons has it ? 



NEPTUNE. 249 

Herschel's mean distance from the Sun is 1828 millions 
of miles ; more than twice the mean distance of Saturn. His 
sidereal revolution is performed in 84 years and 1 month, 
and his motion in his orbit is 15.600 miles an hour. He is 
supposed to have a rotation on his axis, in common with the 
other planets; but astronomers have not yet been able to 
obtain any ocular proof of such a motion. 

His diameter is estimated at 34,000 miles ; which would 
make his volume more than 80 times larger than the Earth's. 
To his inhabitants, the Sun appears only the ^ part as 
large as he does to us; and of course they receive from him 
only that small proportion of light and heat. It may be 
shown, however, that the ^ part of the Sun's light exceeds 
the illuminating power of 800 full Moons. This added to 
the light they must receive from their six satellites, will 
render their days and nigh s far from cheerless. 

The distance from the planet and periodic times of the 
satellites of Herschel, respectively, are as follows: 

Disc in miles. Periodic Times. 

D. H. M. S. 

1. 224.000 5 21 25 20 

2. 29&000 8 

3. 340,000 If 

4. 390,000 11 

5. 777,000 38 

6. 1,556,000 107 



16 


57 


47 


23 


02 


47 


10 


56 


29 


01 


48 


00 


16 


39 


56 



-— LEVERRIER OR NEPTUNE. 

This is the most distant of the primary planets, and in some 
respects one of the most interesting. It is about 40.000 miles 
in diameter, is situated at the mean distance of 2,850,000.000 
miles from the Sun, and revolves around him in 164 years. 
So remote is this newly-discovered member of the solar 
system, that for a body to reach it, moving at rail-road speed, 
or 30 miles an hour, would require more than twenty thousand 
years ! 

The circumstances of the discovery of this planet, are at 

By whom were Herschel's satellites discovered ? What is the distance of Herschel's 
orbit from the Sun ? How much greater is this distance than that of Saturn ? In what 
time is his sidereal revolution performed ? What is the rate per hour of his motion in 
his orbit? Has he a rotation on his avis? What is his diameter estimated to be ? How 
much larger would this make his volume than the Earth? How much less does the 
Sim appear to be to the inhabitants of Herschel. than he does to usi What degree of 
litht and heat do they receive from him. compared with that received by the Earth ? 
To the light of how many full moons is this degree of light equal ■ What is said of the 
distance and magnitude of Neptune ? What is its periodic time? 



250 NEPTUNE. 

once interesting and remarkable. Such is the regularity of 
the planetary motions, that astronomers are enabled to pre- 
dict, with great accuracy, 'heir future places in the heavens, 
and to construct tables, exhibiting their positions for ages to 
come. Soon after the discovery of Herschel. in 1781, his 
orbit was computed, and a table constructed for determining 
his future positions in the heavens, but instead of following 
the prescribed path, or occupying his estimated positions, he 
was found to be yielding to some mysterious and unaccount- 
able influence, under which he was gradually leaving his 
computed orbit, and failing to meet the conditions of the 
tables. 

At first this discrepancy between the observed and the 
estimated places of Herschel, was charged upon the tables, 
and a new orbit and new tables were computed, which it 
was thought could not fail to represent the future places of 
the planet. But these also seemed to be erroneous, as it was 
soon discovered that the computed and observed places did 
not agree, and the difference was becoming greater and 
greater every year. This was an anomaly in the move- 
ments of a planetary body. It was not strange that it should 
be subject to perturbations, from the attractive influence of 
the large planets Jupiter and Saturn, as these were known 
to act upon him. as well as upon each other, and the smaller 
planets, producing perturbations in their orbits, but all this 
had been taken into the account in constructing the tables, 
and still the planet deviated from its prescribed path. To 
charge the discrepancy to the tables, was no longer reason- 
able, though it was thought perhaps sufficient allowance 
had not been made, in their computation, for the disturbing 
influence of Jupiter and Saturn. To determine this ques- 
tion, M. Leverrier of Paris undertook a thorough discussion 
of the subject, and soon ascertained that the disturbing in- 
fluence upon Herschel of all the known planets, was not 
sufficient to account for the anomalous perturbations already 
described, and that they were probably caused by some 
unknown planet, revolving beyond the orbit of Herschel. 
From the amount and effect of this disturbing influence from 
an unknown source, the distance, magnitude, and position 
of the imaginary planet were computed. At this stage of 
the investigation, Leverrier wrote to his friend, Dr. Galle, of 
Berlin, requesting him to direct his telescope to that part of 

How is its vast distance illustrated ? "Who discovered this planet and when 1 Wli it 
circumstances led to ik> discovery, and how was it made? Who tirst saw the limet, 
and how near was it to its computed position .' What other mathematician had com- 
puted its existence, period, d:c " Why, then, was tie not the discoverer.' How many 
satellites has Neptune, and by whom discovered? What is said of the planet's uetnj 
surrounded by riu^s • What reason have we to suppose that the dille "<n bodies 01 thf 
solar system w ere created at the same timu ? 



NEPTUNE. 25 1 

the heavens in which his calculations had located the new 
planet, when lo ! there he lay a thousand millions of miles 
beyond the orbit of Herschel, and yet within less than one 
degree of the place pointed out by Leverrier ! This was on 
the first of September, 1846. 

While M. Leverrier was engaged in his calculations at 
Paris, Mr. Adams, a young mathematician of Cambridge, 
England, was discussing the same great problem, and had 
arrived at similar results even before M. Leverrier, though 
entirely ignorant of each other's labors or conclusions. This 
seems to establish the fact, that the new planet was discov- 
ered by calculation, though the failure of Mr. Adams to pub- 
lish his conclusions, cut off his right to the honor of the dis- 
covery. 

Since the discovery of this planet it has been ascertained 
that it was seen as far back as 1795, though supposed to be 
a fixed star, and catalogued as such, and that all the irregu 
larities of Herschel, with which astronomers were so much 
perplexed, are perfectly accounted for by the influence of 
tlie new planet. 

On the 12th of October, 1846, Mr. Lassell of Starfieid, near 
Liverpool, discovered a satellite attendant upon Leverrier, 
and also, as he supposes, one or more rings similar to those 
of Saturn ; but though the secondary has often been seen by 
others since, and has been made the basis of elaborate cal- 
culations respecting the mass of the primary, no further dis- 
covery of the rings has been made by any other observer. 



Such is the celestial system with which our Earth was 
associated at its creation, distinct from the rest of the starry 
hosts. Whatever may be the comparative antiquity of our 
globe, and the myriads of radiant bodies which nightly gem 
the immense vault above us, it is most reasonable to conclude, 
that the Sun, Earth, and planets, differ little in the date of 
their origin. 

This fact, at least, seems to be philosophically certain, that 
all the bodies which compose our solar system must have 
been placed at one and the same time in that arrangement, 
and in those positions in which we now behold them; because 
all maintain their present stations, and motions, and distances, 
by their mutual action on each other. Neither could it be 
where it is, nor move as it does, nor appear as we see it 
unless they were all co-existent. The presence of each is 
essential to the system — the Sun to them, they to the Sun, 
and all to each other. This fact is a strong indication that 
their formation was simultaneous. 



252 COMETS. 

COMETS. 

Comets, whether ^viewed as ephemeral meteors, or as 
substantial bodies, forming a part of the solar system, are 
objects of no ordinary interest. 

When, with uninstructed gaze, we look upwards, to the 
clear sky of evening, and behold, among the multitudes of 
heavenly bodies, one. blazing with its long train of light, 
and rushing onward towards the center of our system, we 
insensibly shrink back as if in the presence of a supernatu- 
ral being. 

But when, with the eye of astronomy, we follow it through 
its perihelion, and trace it far off, beyond the utmost verge 
of the solar system, till it is lost in the infinity of space, not 
to return for centuries, we are deeply impressed with a sense 
of that power which could create and set in motion such 
bodies. 

Comets are distinguished from the other heavenly bodies, 
by their appearance and motion. The appearance of the 
planets is globular, and their motion around the Sun is nearly 
in the same plane, and from west to east; but the comets 
have a variety of forms, and their orbits are not confined to 
any particular part of the heavens ; nor do they observe any 
one general direction. 



ORBIT OP A COMET. 




The orbits of the planets approach nearly to circles, while 
those of the comets are very elongated ellipses. A wire 
hoop, for example, will represent the orbit of a planet. If 

"What feelings does the contemplation of comet.s naturally excite 1 How are comcta 
distinguished from the other heavenly bodies ? Describe their appearance and motion. 
at what three parts may comets be considered to be compo» d i Descrilte themj uurl» 
icverelly. 



COMETS. 253 

two opposite sides of the same hoop be extended, so that it 
shall be long and narrow, it will then represent the orbit of 
a comet. The Sun is always in one of the foci of the comet's 
orbit. 

There is, however, a practical difficulty of a peculiar nature which embar- 
rasses the solution of the question as to the form of the conietary orbits. It so 
happens that the only part of the course of a comet which can ever be visible, 
is a portion throughout which the ellipse, the parabola, and hyperbola, so 
closely resemble each other, that no observations can be obtained with sufficient 
accuracy to enable us to distinguish them. In fact, the observed path of any 
comet, while visible, may belong either to an ellipse, parabola, or hyperbola. 

That part which is usually brighter, or more opaque, than 
the other portions of the comet, is called the nucleus. This 
is surrounded by an envelope, which has a cloudy, or hairy 
appearance. These two parts constitute the body, and, in 
many instances, the whole of the comet. 

Most of them, however, are attended by a long train, called 
the tail; though some are without this appendage, and as 
seen by the naked eye, are not easily distinguished from the 
planets. Others again, have no apparent nucleus, and seem 
to be only globular masses of vapor. 

Nothing is known with certainty of the composition of 
these bodies. The envelope appears to be nothing more 
than vapor, becoming more luminous and transparent when 
approaching the Sun. As the comets pass between us and 
the fixed stars, their envelopes and tails are so thin, that 
stars of very small magnitudes may be seen through rhem. 
Some comets, having no nucleus, are transparent throughout, 
their whole extent. 

The nucleus of a comet sometimes appears opaque, and 
it then resembles a planet. Astronomers, however, are not 
agreed upon this point. Some affirm that ihe nucleus is 
always transparent, and that comets are in fact nothing but 
a mass of vapor, or less condensed at the center. By others 
it is maintained that the nucleus is sometimes solid and 
opaque. It seems probable, however, that there are three clas- 
ses of comets ; viz.: 1st, Those which have no nucleus, being 
transparent throughout their whole extent ; 2d, Those which 
have a transparent nucleus ; and. 3d, Those having a nu- 
cleus which is solid and opaque. 

A comet, when at a distance from the Sun, viewed through 
a good telescope, has the appearance of a dense vapor sur- 
rounding the nucleus, and sometimes flowing far into the 
regions of space. As it approaches the Sun, its light be- 
comes more brilliant, till it reaches its perihelion, when its 

Have all comets these three parts? "What apparent differences may be perceived in 
the composition of different comets ? Into what classes, with referunce to their com- 
Mgition, may comets be divided? Describe the different appea r ances of comets at 
different distances from the Sun. In what part of their orbit are their phenoroci.a seen 
to the beiil advantage ? 

22 



254 COMETS. 

light is more dazzling than that of any other celestial body, 
the Sun excepted. In this part of its orbit are seen to the 
best advantage the phenomena of this wonderful body, which 
has, from remote antiquity, been the spectre of alarm and 
terror. 

COMETS OF 16S9 AND 1744. 




The luminous train of a comet usually follows it, as i 
approaches the Sun, and goes before it, when the comet 
recedes from the Sun: sometimes the tail is considerably 
curved towards the region to which the comet is tending, 
and in some instances, it has been observed to form a right 
angle with a line drawn from the Sun through the center 
of the comet. The tail of the comet of 1744, formed nearly 
a quarter of a circle ; thai of 16S9 was curved like a Turkish 
sabre. Sometimes the same comet has several tails. That 
of 1744 had, at one time, no less than s<>, which appeared 
and disappeared in a few days. The comet of 1S23 had, for 
several days, two tails; one extending towards the Sun, and 
the other in the opposite direction. 

Comets, in passing among and near the planets, are ma- 
f erially drawn aside from their courses, and in some cases 
have their orbits entirely changed. This is remarkablv frue 
in regard to Jupiter, which seems by some strange fatality 
to be constantly in their way, and to serve as a perpetual 
stumbling-block to them. 

Wh't is usually the direction of the luminous train' What was the direction of 
the tail of the comet of 1744 ? What was the direction of the tail of the com* 
Hmv many tails had the comet of 1744 at one time, and how lone did they continue 
to appear ' How many had that of IS'^3. and what was their diiection ! When comett 
[•ass near planets, how does the attraction of the planets affect them' In regard to 
what planet is this remarkably true ) Mention an example of eomois being so affected. 



COMETS. 255 

"The remarkable comet of 1770, which was found by Lexell to revolve in 
a moderate ellipse, in aperiod of about five years, actually got entangled among 
the satellites of Jupiter, and thrown out of its orbir by the attractions of that 
planet," and has not been heard of since. — Herschel. p. 310. By this extraor- 
dinary rencontre, the motions of Jupiter's satellites suffered not the least percep- 
tible derangement ; a sufficient proof of the aeriform nature of the cornel's 
mass. 

It is clear from observation, that comets contain very little 
matter. For they produce little or no effect on the motion 
of the planets when passing near those bodies ; it is said 
that a comet, in 1454, eclipsed the moon ; so that it must 
have been very near the Earth ; yet no sensible effect was 
observed to be produced by this cause, upon the motion of 
the Earth or the Moon. 

The observations of philosophers upon comets, have as 
yet detected nothing of their nature. Tycho Brahe and 
Appian, supposed their tails to be produced by the rays of 
the Sun transmitted through the nucleus, which they sup-« 
posed to be transparent, and to operate as a lens. Keplei 
thought they were occasioned by the atmosphere of the 
comet, driven off by the impulse of the Sun's rays. This 
opinion, with some modification, was also maintained by 
Euler. Sir Isaac Newton conjectured, that they were a 
thiii vapor, rising from the heated nucleus, as smoke ascends 
from the Earth ; while Dr. Hamilton supposed them to be 
streams of electricity. 

" That the luminous part of a comet," says Sir John Herschel. ' ; is something 
In the nature of a smoke, fog, or cloud, suspended in a transparent atmos- 
phere, is evident from a fact which has been often noticed, •viz., that the por- 
tion of the tail where it comes up to. and surrounds the head, is yet separated 
from it by an interval less luminous; as we often see one layer of clouds laid 
over another with a considerable clear space between them." ' And again : •• It 
follows that these can only be regarded as great masses of thin vapor, suscep- 
tible of being penetrated through their whole substance by the sunbeams." 

Comets have always been considered by the ignorant and 
superstitious, as the harbingers of war. pestilence, and famine. 
Nor has this opinion been, even to this day. confined to the 
unlearned. It was once universal. And when we examine 
the dimensions and appearances of some of these bodies, we 
cease to wonder that they produced universal alarm. 

According to ihe testimon}^ of the early writers, a comet 
which could be seen in day-light with the naked eye, made 
its appearance 43 years before the birth of our Saviour. 
This date was just after the death of Ccesar, and by the 
Romans, the comet was believed to be his metamorphosed 
soul, armed with fire and vengeance. This comet is again 
mentioned as appearing in 1U)6, and then resembling the 

What fact connected itrith this cave proves the aeriform nature of the comet's >uaei 
How is it clear from observation that comets contain very little ixatter • Wlial were 
the opinion* of Tycho Bruhe. Appian. Kepler, Euler. Sir Isaac Newton, and Dr. il i nil- 
ton, in regard to the tails of cornels > What was the opinitm of Sir John Her- 
n tehal founded? How have comets been regarded by the ignorant and superstitious? 



256 COMETS. 

Sun in brightness, being of a great size, and having an im- 
mense tail. 

In the year 1402, a comet was seen, so brilliant as to be 
discerned at noon-day. 

In 1456, a large comet made its appearance. It spread 
a wider terror than was ever known before. The belief was 
very general, among all classes, that the comet would de- 
s:roy the Earth, and that the Day of Judgment was at hand! 

This comet appeared again in the years 1531, 1G07. 16&?, 1753, and 1836. It 
passed its perihelion in November, 1835, and will reappear every 75j years 
thereafter. 

At the time of the appearance of this comet, the Turks 
extended their victorious arms across the Hellespont, and 
seemed destined to overrun all Europe. This added not a 
little to the general gloom. Under all these impressions, 
the people seemed totally regardless of the present, and 
anxious only for the future. The Romish Church held at 
this time unbounded sway over the lives, and fortunes, and 
consciences of men. To prepare the world for its expected 
doom. Pope Calixtus III. ordered the Ave Maria to be re- 
peated three times a day, instead of two. He ordered the 
church bells to be rung at noon, which was the origin of 
that practice, so universal in Christian churches. To the 
Ave Maria, the prayer was added — " Lord, save us from 
the Devil, the Turk, and the Comet:" and once, each day, 
these three obnoxious personages suffered a regular excom- 
munication. 

The pope and clergy exhibiting such fear, it is not a mat- 
ter of wonder that it became the ruling passion of the multi- 
tude. The churches and convents were crowded for confes- 
sion of sins; and treasures uncounted were poured into the 
Apostolic chamber. 

The comet, after suffering some months of daily cursing 
and excommunication, began to show signs of retreat, and 
soon disappeared from those eyes in which it found no favor. 
Joy and tranquillity soon returned to the faithful subjects of 
the pope, but not so their money and lands. The people, 
however, became satisfied that their lives, and the safety of 
the world, had been cheaply purchased. The pope, who had 
achieved so signal a victory over the monster of the sky, had 
checked the progress of the Turk, and kept, for the present, 
his Satanic majesty at a safe distance ; while the Church of 
Rome, retaining her unbounded wealth, was enabled to con- 
tinue that influence over her followers, which she retains, in 
part, to this day. 

Mention some ot the most remarkable comets which have appeared. Describe them 
severally, and relate in what manner they were severally regarded. What is the periodic 
fe'Mi* of (his rnnw.t ' 



COMETS. 257 

GREAT COMET OF 16S0. 




The comet of 16S0 would have been still more alarming 
than that of 1456, had not science robbed it of its terrors, 
and history pointed to the signal failure of its predecessor. 
This comet was of the largest size, and had a tail whose 
enormous length was more than ninety-six millions of miles. 

At its greatest distance, it is 13,000 millions of miles from 
the Sun ; and at its nearest approach, only 574,000 miles 
from his center ; * or about 130.000 miles from his surface. 
In that part of its orbit which is nearest the Sun. it flies 
with the amazing swiftness of 1.000,000 miles in an hour, 
and the Sun, as seen from it, appears 27.000 times larger 
than it appears to us ; consequently, it is then exposed to a 
heat 27,000 times greater than the solar heat at the Earth. 
This intensity of heat exceeds, several thousand times, that 
of red-hot iron, and indeed all the degrees of heat that we 
are able to produce. A simple mass of vapor, exposed to a 

* In Brewster's edition of Ferguson, this distance is stated as only 49,000 miles. This 
is evidently a mistake; for if the comet approached the Sun's center within 49,000 miles, 
it would penetrate 390.000 miles below the surface! Taking Ferguson's own elements 
for computing the perihelion distance, the result will be 494,460 miles. The mistake 
may be accounted tor by supposing that the cipher had been omitted in the copy, and 
the period pointed oft' one figure tarther to the left. Yet, with this alteration, it would 
still be incorrect; because the Earth's mean distance from the tiun. which is the inte- 
ger of this calculation, is assumed at Si. 000,000 of miles. The ratio of the comet's peri- 
helion distance from the Sun. to the Earth's mean distance, as giveu by M. Pingre, is as 
0.00603 to I. This multiplied into 95.273.S69. cives 5T4.50U miles lor the comet's perihelion 
distance from the Sun's center: from which, if we subtract his semi diameter, 443.840 
miles, we shall have 130,660 miles, the distance of the comet from the surface of the 
Sun. 

Again, if we divide the Earth's mean distance from the Sun, by the comet's perihe- 
lion distance, we shall find that the latter isoniy l-166th part of the Earths distance. 
Now the square of 166 is 27,556; and this expresses the number of time- that die Sun 
appears larger to the comet, in the above situation, than it does to the Earth. Squire 
makes it 34.596 times larger. 

According to Newton, the velocitv is SS0.000 miles >er hour. More recent discoveries 
indicate a velocity oll,240,ios m:les \ er hour. 

22* 



258 COMETS. 

thousandth part of such a heat, would be at once dissipated 
in .-pace — a pretty strong indication that, however volatile 
are the elements of which comets are composed, they are, 
nevertheless, capable of enduring an inconceivable intensity 
of both heat and cold. 

This is the comet which, according to the reveries of Dr. 
Whiston and others, deluged the world in the time of Noah. 
Whiston was the friend and successor of Newton: but, anx- 
ious to know more than is revealed, he passed the bounds 
of sober philosophy, and presumed not only to fix the resi- 
dence of the damned, but also the nature of their punish- 
ment. According to his theory, a comet was the awful 
prison-house in which, as it wheeled from the remotest re- 
gions of darkness and cold into the very vicinity of the Sun, 
hurrying its wretched tenants to the extremes of perishing 
cold and devouring fire, the Almighty was to dispense the 
severities of his justice. 

Such theories may be ingenious, but they have no basis 
of facts to rest upon. They more properly belong to the 
chimeras of Astrology, than to the science of Astronomy. 

When we are told by philosophers of great caution and 
high reputation, that the fiery train of the comet, just alluded 
to. extended from the horizon to the zenith ; and that that 
of 1744 had, at one time, six tails, each 6,000,000 of miles 
long, and that another, which appeared soon after, had one 
40.000,000 of miles long, and when we consider also the in- 
conceivable velocity with which they speed their flight 
through the solar system, we may cease to wonder if, in the 
darker ages, they have been regarded as evil omens. 

But these idle fantasies are not peculiar to any age or 
country. Even in our own times, the beautiful comet of 
1811, the most splendid one of modern times, was generally 
considered among the superstitious, as the dread harbinger 
of the war which was declared in the following spring. It 
is well known that an indefinite apprehension of a more 
dreadful catastrophe lately pervaded both continents, in 
anticipation of Biela's comet of 1832. 

The nucleus of the comet of 1811, according to observa- 
tions made near Boston, was 2.617 miles in diameter, cor- 
responding nearly to the size of the Moon. The brilliancy 
with which it shone, was equal to one tenth of that of the 



What is the degree of heat to which the comet of 1630 is exposed, when in it* perihe- 
lion, compared to that experienced at the Earth ? What is the intensity of such a drtrree 
of heat, compared with that of red-hot iron, or with any degree of heat which we are 
able to produce ? What inference may be derived from this lact in regard to the com- 
position of comets? What were the reveries of Dr. Whiston and others in regard to this 
comet ? What facts oupht to make us cease to wonder that comets were in darker age» 
considered as harbingers of evil ? Have these fantasies, however, been confined to the 
darker ages .' Of what event was the comet of 1811 considered, in our country, to be the 
harbinger ? 



COMKTS. 259 

Moon. The envelope, or aeriform covering, surrounding 
the nucleus, was 24,000 miles thick, about five hundred times 
as thick as the atmosphere which encircles the Earth ; ma- 
king the diameter of the comet, including its envelope, 50,617 
miles. It had a very luminous tail, whose greatest length 
was one hundred million of miles. 

C0MET3 OF 1811 AND 1S 1 9 




This comet moved, in us perihelion, with an almost inconceivable velocity — 
fifteen hundred times greater than that of a ball burstins from the mouth of a 
cannon. According to Regiomontanus, the comet of 1472 moved over an arc 
of 120° in one day. Brydone observed a comet at Palermo in 1770, which pass- 
ed through 50° of a great circle in the heavens in 24 hours. Another comet, 
which appeared in 1759, passed over 41° in the same time. The conjecture of 
Dr. Halley therefore seems highly probable, that if a body of such a size, hav- 
ing any considerable density, and moving with such a velocity, were to strike 
our Earth, it would instantly reduce it to chaos, mingling its elements in ruin. 

The transient effect of a body passing near the Earth, could scarcely amount 
to any great convulsion, says Dr. Brewster ; but if the Earth were actually to 
receive a shock from one of these bodies, the consequences woufd be awful. 
A new direction would be given to its rotary motion, and it would revolve 
around a new axis. The seas, forsaking their beds, would be hurried, by their 
centrifugal force, to the new equatorial regions : islands and continents, the 
abodes of men and animals, would be covered by the universal rush of the 
waters to the new equator, and every vestige of human industry and genius 
would be at once destroyed. 

The chances against such an event however, are so very- 
numerous, that there is no reason to dread its occurrence. 

Describe this comet. Give some, examples of the velocity of comets. What icoula 
probably be the effect upon the Earth, should a comet strike it ? What dees Dr. Breto 
iter say xcould be the effect of a comet passing near the Earth ? But if the Earth were 
aetuaUy to r'£eive a shock from a comet, what does fie say would be the results? 



260 COMETS. 

The French government not long since, called the attention 
of some of her ablest mathematicians and astronomers to 
the solution of this problem ; that is, to determine, upon 
mathematical principles, how many chances of collision the 
Earth was exposed to. After a mature examination, they 
reported—" We have found that, of 281.000,000 of chances, 
'there is only one unfavorable — there exists but one which 
can produce a collision between the two bodies." 

" Admitting, then," say they, "for a moment, that the comets which may 
strike the Earth with their nucleuses:, would annihilate the whole human race; 
the danger of death to each individual, resulting from the appearance of an un- 
known comet, would be exactly equal to the risk he would run, if in an urn 
there was only one single white ball among a total number of 281.000.00IJ balls, 
and that his condemnation to death would be the inevitable consequence of the 
white ball.being produced at the first drawing." 

We have before stated that comets, unlike the planets, 
observe no one direction in their orbits, but. approach to. and 
recede from their great center of attraction, in every possible 
direction. Nothing can be more' sublime, or better calcula- 
ted to fill the mind with profound astonishment, than to con- 
template the revolution of comets, while in that part of their 
orbits which comes within the sphere of the telescope. Some 
seem to come up from the immeasurable depths below the 
ecliptic, and. having doubled the heavens' mighty cape, again 
plunge downward with their fiery trains, 

" On the long travel of a thousand years." 

Others appear to come down from the zenith of the uni- 
verse to double their perihelion about the Sun, and then re- 
ascend far above all human vision. 

Others are dashing through the solar system in all possi- 
ble directions, and apparently without any undisturbed or 
undisturbing path prescribed by Him who guides and sus- 
tains them all. 

Until within a few years, it was universally believed that 
the periods of their revolutions must necessarily be of prodi- 
gious length; but within a few years, two comets have been 
discovered, whose revolutions are performed, comparatively, 
Within our own neighborhood. To distinguish them from 
the more remote, they are denominated the comets of a short 
period. The first was discovered in the constellation Aqua- 
rius, by two French astronomers, in the year 1786. The 
same comet was again observed by Miss Caroline Herschel, 
in the constellation Cygnus, in 1795, and again in 1805. In 
1818, Professor Encke determined the dimensions of its orbit, 

How did the French mathematicians and astronomers find the chances of a collision be- 
tween the Earth and comets to stand > What, on the supposition that a stroke >.' 
would annihilate the xohole human race, is the danger of death to each individual, 
resulting from the appearance of an unknown comet ? 

What is the directiww of comets in their orbit- ! What has been, until within a f«v» 
years, the universal opinion in regard to the length of the times of iheir revolution t 
Why doea not the samu opinion prevail now ? What are these two comets denominated'' 



encke's comet. 261 




and the period oi its sidereal revolution; i'or which reason i 
has been called ' Encke's Comet.''' 

This comet performs its revolution around the Sun in about 
3 years and 4 months, in an elliptical orbit which lies wholly 
within the orbit of Jupiter. Its mean distance from the Sun 
is 212 millions of miles ; the eccentricity of its orbit is 179 
millions of miles; consequently, it is 358 millions of miles 
nearer the Sun in its perihelion, than it is in its aphelion. It 
was visible throughout the United States in 1825, when it 
presented a fine appearance. It was also observed at its 
next return in 1828 ; but its return to its perihelion, on the 
6th of May, 1832, was invisible in the United States, on 
account of its great southern declination. It has returned 
at regular periods since that time. 

The second " Comet of a short period," was observed in 
1772 ; and was seen again in 1805. It was not until its re- 
appearance in 1826, that astronomers were able to deter- 
mine the elements of its orbit, and the exact period of its 
revolution. This was successfully accomplished by M. Biela 
of Joscphstadt; hence it is called BieWs Comet. According 
to observations made upon it in 1805, by the celebrated Dr. 
Olbers, its diameter, including its envelope, is 42.2S0 miles. 
It is a curious fact, that the path of Biela's comet passes 
very near to that of the Earth; so near, that at the moment 

Relate the history of the discovery of the first. Why is it called Encke's comet ? What 
is the time of the revolution of Encke's comet? What is the form of its orbit, and what 
its position with regard to the orbit of Jupiter? What is this couiet's mean distance from 
the Sun ? What is the eccentricity of its orbit? 

How much nearer the Sun, then, is the comet, when in its perihelion than when in 
its aphelion ? In what years has this comet been seen in the United States > Why was 
it not visible in the United States at the time of its return in 1832 ? Relate the history 
of the discovery of the second comet of a short period. Why is it called Biela's combU 



262 COMETS. 

the center of the comet is at the point nearest to the EaHh's 
path, the matter of the comet extends beyond that path, and 
includes a portion within it. Thus, if the Earth were at that 
point of its orbit which is nearest to the path of the comet, at 
the s;ime moment that the comet should be at that point of 
its orbit which is nearest to the path of the Earth, the Earth 
would be enveloped in the nebulous atmosphere of the comet. 

With respect to the effect which might be produced upon 
our atmosphere by such a circumstance, it is impossible to 
offer any ihing but the most vague conjecture. Sir John 
Herschel was able to distinguish stars as minute as the 16th 
or 17th magnitude through the body of the comet! Hence it 
seems reasonable to infer, that the nebulous matter of which 
it is composed, must be infinitely more attenuated than our 
atmosphere ; so that for every particle of cometary matter 
which we should inhale, we should inspire millions of parti- 
cles of atmospheric air. 

This is the comet which was to come into collision with 
the Earth, and to blot it out from the Solar System. In re- 
turning to its perihelion, November 26th, 1832, it was com- 
puted that it would cross the Earth's orbit at a distance of 
only 18,500 miles. It is evident that if the Earth had been 
in that part of her orbit at the same time with the comet, 
our atmosphere would have mingled with the atmosphere 
of the comet, and the two bodies, perhaps, have come in 
contact. But the comet passed the Earth's orbit on the 29th 
of October, in the 8th degree of Sagittarius, and the Earth 
did not arrive at that point until the 30th of November, which 
was 32 days afterwards. 

If we multiply the number of hours in 32 days, by 68,000 
(the velocity of the Earth per hour), we shallfind that the 
Earth was more than 52.000,000 miles behind the comet 
when it crossed her orbit. Its nearest approach to the Earth, 
at any time, was about 51 millions of miles ; its nearest ap- 
proach to the Sun, was about S3 millions of miles. Its mean 
distance from the Sun, or half the longest axis of its orbit, 
is 337 millions of miles. Its eccentricity is 253 millions of 
miles ; consequently, it is 507 millions of miles nearer the 
Sun in its perihelion than it is in its aphelion. The period 
of its sidereal revolution is 2,460 days, or about 6? years. 

The following representation of the entire orbit of Biela'a 

What, according to ihe observations of Or Olbers in 1S05, was the diameter of Biela's 
comet, including the envelope i How neurdoes the path of Biela's comet lie to that of 
the Earth ! What would be the ertewt upon our atmosphere would the nebulous at- 
mosphere of the comet envelope it* What reason have we to suppose that it is more 
attenuated than our atmosphere? It was predicted that this comet wouid come into 
collision with the Earth ; W hat were the grounds of probability th;it such an event would 
take place, and why did it not ' Wh;it was its nearest approach to the Karth at i-uy time 1 
What it* nearest approach to the Snn 1 "What ,ts mean distance from the nun ? What 
its eccentricity' What, then, i* the difference between its perihelion and aphelio* 
distances? What is the period of its sidereal revolution ? 



COMETS. 263 

comet, was obtained from the Astronomer Royal of the 
Greenwich Observatory. It shows not only the space and 
position it occupies in the solar system, but the points where 
its orbit intersects ail the planetary orbits through which it 
passes. By this, it is seen that its perihelion lies between 
the orbits of the Earth and Venus, while its aphelion extends 
a little beyond that of Jupiter. 

ORBIT OF EIELA'S COMET. 




264 COMETS. 

Although the comets of Eneke and Biela are objects of very great interest, 
yet their short periods, the limited space within which their motion is circum- 
scribed, and consequently the very slight disturbance which they sustain from 
the attraction of the planets, render them of less interest to physical astronomy 
than those of longer periods. 

They do not, like them, rush from the invisible and inaccessible depths of 
space, and. after sweeping our system, depart to distances with the conception 
of which the imagination itself is confounded. They possess none of that gran- 
deur which is connected with whatever appears to break through the fixed or- 
der of the universe. It is reserved for the comet of Halley alone to afford the 
proudest triumphs to those powers of calculation by which we are enabled to 
follow it in the depths of space, two thousand millions of miles beyond the ex- 
treme verge of the solar system ; and, notwithstanding disturbances which ren- 
der each succeeding period of its return different from the last, to foretell tltal 
return with precision. 

To be able to predict the very day a.id circumstances of 
the return of such a bodiless and eccentric wanderer, after 
the lapse of so many years, evinces a perfection of the as- 
tronomical calculus that may justly challenge our admiration. 

" The re-appearance of this comet," says Herschel, " whose 
return in 1832 was made the subject of elaborate calculations 
by mathematicians of the first eminence, did not disappoint 
the expectation of astronomers. It is hardly possible to 
imagine any thing more striking than the appearance, after 
the lapse of nearly seven years, of such an all but impercep- 
tible cloud or wisp of vapor, true, however, to its predicted 
time and place, and obeying laws like those which regulate 
the planets." 

Herschel, whose Observatory is at Slough, England, observed the daily pro- 
gress of this comet from the 24th of September, until its disappearance," com- 
pared its actual position from day to day with its calculated position, and found 
them to agree within four or five minutes of time in right ascension, and within 
a Jew seconds of declination. Its position, then, as represented on a planis- 
phere which the author prepared for his pupils, and afterwards published, 
was true to within a less space than one third of its projected diameter. Like 
some others that have been observed, this comet has no luminous train by 
which it can be easily recognized by the naked eye, except when it is very near 
the Sun. This is the reason why it was not more generally observed at its late 
return. 

Although this comet is usually denominated "Biela's comet," yet it seems 
that M. Gambart, director of the Observatory at Marseilles, is equally entitled 
to the honor of identifying it with the comet of 1772. and of 1S05. He dis 
t only 10 days after Biela, and immediately set about calculating its element* 
from his own observations, which are thought to equal, if they do not sur 
pass, in point of accuracy, those of every other astronomer. 

Up to the beginning of the 17th century, no correct no- 
tions had been entertained in respect lo the paths of comets. 
Kepler's first conjecture was that they moved in straight 
lines ; but as that did not agree with observation, he next 
concluded that they were parabolic curves, having the Sun 

Why are the cornets of Encke and Biela e 'jecta often interest to physical astronotny 
than those of longer period* ? What is the situation of the orbit of Jiiela's comet in the 
lolar system ? When will it return again ' How t/iuch did its actual rmition from day to 
day, as observed by Herschel, differ from its ca'culatcd position ) n'hy irat it not mere 
generally observed at its late return! What astronomer besides Bitta identified it 
tcith the comet of 1772 and 1805 ! What were the opinions of astronomers in rcs.ird to 
the paths »f comets, up to the beginning of the I7ih ceutury.' What were > 
•"jinions on this suoject" 



COMETS. 265 

near the vertex, and running indefinitely into the regions of 
space at both extremities. There was nothing in the ob- 
servations of the earlier astronomers to fix their identity, or 
to lead him to suspect that any one of them had ever been 
seen before ; much less that they formed a part of the solar 
system, revolving about the Sun in elliptical orbits that re- 
turned into themselves. 

This grand discovery was reserved for one of the most 
industrious and sagacious astronomers that ever lived — this 
was Dr. Halley, the contemporary and friend of Newton. 
When the comet of 1682 made its appearance, he set him- 
self about observing it with great care, and found there was 
a wonderful resemblance between it and three other comets 
that he found recorded, the comets of 1456, of 1531, and 
1607. The times of their appearance had been nearly at 
equal and regular intervals; their perihelion distances were 
nearly the same ; and he finally proved them to be one and 
the same comet, performing its circuit around the Sun in a 
period varying a little from 76 years. It is therefore ct lied 
Halley* s comet. 

h alley's comet. 1632. 




This is me very same comet that tilled the eastern world 
with so much consternation in 1436, and became an object 
of such abhorrence to the church of Rome. 



iner by which he c 



23 



266 COMETS. 

The periodic times of the three comets just described, are 
as follows: 

Encke's, 1212 days. 
Biela's, 2461 ' ; 
Halley's, 28,000 days. 

Halley's cornet, true to its predicted time and place, is now (Oct. 1835) visible 
in the evening sky. But we behold none of those phenomena which threw our 
ancestors of the middle ages into agonies of superstitious terror. We see not the 
cometa horrendce ma°;nitudinis, as it appeared in 1305. nor that tail of enor- 
mous length which, in 1456, extended over two thirds of the interval between 
the horizon and the zenith, nor even a star as brilliant as was the same comet in 
1682, with its tail of 30°. 

Its mean distance from the Sun is 1,713,700.000 miles ; the eccentricity of its 
orbit is 1,658,000,000 miles ; consequently it is 3,316,000,000 miles farther from 
the Sun in its aphelion than it is in its perihelion. In the latter case its distance 
from the Sun is only 55,700.000 miles ; but in the former it is 3,371,700,000 miles. 
Therefore, though its aphelion distance be great, its mean distance is less than 
that of Herschel; and great as is the aphelion distance, it is but a very small 
fraction less than one fixe thousandth part of that distance from the Sun, beyond 
which the very nearest of the fixed stars must be situated; and, as the deter- 
mination of their distance is negative and not positive, the nearest of them may 
be at twice or ten times that distance. 

The number of comets which have been observed since the Christian era, 
amounts to 700. Scarcely a year has passed without the observation of one or 
two. And since multitudes of them must escape observation, by reason of 
their traversing that part of the heavens which is above the horizon in the day 
time, their whole number is probably many thousands. Comets so circum- 
stanced, can only become visible by the rare coincidence of a total eclipse of 
the Sun — a coincidence which happened, as related by Seneca, 60 years before 
Christ, when a large comet was actually observed very near the Sun. 

ButM. Arasro reasons in the following manner, with respect to the number 
of comets :— The number of ascertained comets, which, at their least distances, 
pass within the orbit of Mercury, is thirty. Assuming that the comets are uni- 
formly distributed throughout the solar system, there will be 117,649 times as 
many comets included within the orbit of Herschel, as there are within the 
orbit of Mercury. But as there are 30 within the orbit of Mercury, there must 
be 3.529,470 within the orbit of Herschel ! 

Of 97 comets whose elements have been calculated by astronomers. 24 passed 
between the Sun and the orbit of Mercury ; 33 between the orbits of Mercury 
and Venus ; 21 between the orbits of Venus and the Earth ; 15 between the 
orbits of Ceres and Jupiter. 49 of these comets move from east towest, and 
49 in the opposite direction. 

The total number of distinct comets, whose paths during the visible part of 
their course had been ascertained, up to the year 1S32, was one hundred and 
thirty-seven. 

What regions these bodies visit, when they pass beyond 
the limits of our view ; upon what errands they come, when 
they again revisit the central parts of our system ; what in 
the difference between their physical constitution and that 
of the Sun and planets ; and what important ends they are 
destined to accomplish, in the economy of the universe, are 

In what time do the three cornels ju*t described accomplish their respective revolu- 
tions? What comet was visible (Oct. 1835)? What are the mean, and the aphelion and 
perihelion distances of Halley's comet from the Sun? What fart of the distance be- 
yond tohich the near « .' (f the fixed stars must be placed, is its aphelion distance? 
What is the number of comets which have been observei since the Christian era? 
Why must some of them escape observation ? How great is probably their actual num- 
ber f In tohat case alone can comets tohich traverse the horizon in the day lime beeem* 
visible ? Mtntion an instance of a comet thus becoming visible. What is the. reason- 
ing ofM. Arago in regard to the n umber of comets ? Describe the track ammg the orbitt 
tfthe planets' of the 97 comets whose elements have been calculated by astronomer*. In 
tohat direction do they move ? What, up to Die year 1832, was the whole number of dis- 
tinct comets, whosepath, during the visible pail of their course, has been determined? 



LAW OF UNIVERSAL GRAVITATION. 267 

inquiries which naturally arise in the mind, but which sur- 
pass the limited powers of the human understanding at pre- 
sent to determine. 



CHAPTER XX. 

OF THE FORCES BY WHICH THE PLANETS 
ARE RETAINED IN THEIR ORBITS. 

Having described the real and apparent motions of the 
bodies which compose the solar system, it may be interesting 
next to show, that these motions, however varied or complex 
they may seem, all result from one simple principle, or law, 
namely, the 

LAW OF UNIVERSAL GRAVITATION. 

It is said, that Sir Isaac Newton, when he was drawing 
to a close the demonstration of the great truth, that gravity 
is the cause which keeps the heavenly bodies in their orbit3, 
was so much agitated with the magnitude and importance 
of the discovery he was about to make, that he was unabje 
to proceed, and desired a friend to finish what the intensity 
df his feelings did not allow him to do. By gravitation is 
meant, that universal law of attraction, by which every par 
tide of matter in the system has a tendency to every other 
particle. 

This attraction, or tendency of bodies towards each other, 
is in proportion to the quantity of matter they contain. The 
Earth, being immensely large in comparison with all other 
substances in its vicinity, destroys the effect of this attrac- 
tion between smaller bodies, by bringing them all to itself. 

The attraction of gravitation is reciprocal. All bodies not 
only attract other bodies, but are themselves attracted, and 
both according to their re-spective quantities of matter. The 
Sun, the largest body in our system, attracts the Earth and 
all the other planets, while they in turn attract the Sun. 
The Earth, also, attracts the Moon, and she in turn attracts 
the Earth. A ball, thrown upwards from the Earth, is 
brought again to its surface ; the Earth's attraction not only 
counterbalancing that of the ball, but also producing a mo- 
tion of the ball towards itself. 

By what principle, or kiw, are the planets retained in their orbits? "Who discovered 
this great truth, and how was he affected in view ol' it,' What is meant by gravi- 
tation ? To what is it proportioned ? Give some example. How i-- it known tnat the 
attraction of gravitation is reciprocal i Give some examples to illustrate this principle. 



268 LAW OF UNIVERSAL GRAVITATION. 

This disposition, or tendency towards the Earth, is mani- 
fested in whatever tails, whether it be a pebble from the 
hand, an apple from a tree, or an avalanche from a moun- 
tain. All terrestrial bodies, not excepting the waters of the 
ocean, gravitate towards the center of the Earth, and it is 
by the same power that animals on all parts of the globe 
stand with their feet pointing to its center. 

The power of terrestrial gravitation is greatest at the 
Earth's surface, whence it decreases both upwards and 
downwards; but not both ways in the same proportion. It 
decreases upwards as the square of the distance from the 
Earth's center increases ; so that at a distance from the 
center equal to twice the semi-diameter of the Earth, the 
gravitating force would be only one fourth of what it is at 
the surface. But below the surface, it decreases in the direct 
ratio of* the distance from the center; so that at a distance 
of half a semi-diameter from the center, the gravitating force 
is but half of what it is at the surface. 

Weight and Gravity, in this case, are synonymous terms 
We say a piece of lead weighs a pound, or 16 ounces; bul 
if by any means it could be raised 4000 miles above the sur- 
face of the Earth, which is about the distance of the surface 
from the center, and consequently equal to two semi-diame- 
ters of the Earth above its center, it would weigh only one 
fourth of a pound, or four ounces; and if the same weight 
could be raised to an elevation of 12,000 miles above the 
surface, or four semi-diameters above the center of the Earth, 
it would there weigh only one sixteenth of a pound, or one 
ounce. 

The same body, at the center of the Earth, being equally 
attracted in every direction, would be without weight; at 
1000 miles from the center it would weigh one fourth of a 
pound ; at 2000 miles, one half of a pound ; at 3000 miles, 
three fourths of a pound ; and at 4000 miles, or at the sur- 
face, one pound. 

It is a universal law of attraction, that its potter decreases as the square of 
the distance increases. The converse of this is also true, viz. : The power in- 
creases as the square of the distance decreases. Giving to this law the form of 
a practical rule, it will stand thus: 

The gravity of bodies above the surface of the Earth decreases in a duj/li- 
cate ratio (or as the squares of their distances), in semi-diameters of the Earth, 
from the Earth's center. That is, when the gravity is increasing, multiply 
the weight by the square of the distance; but when the gravity is decreasing, 
divide the weight by the square of the distance. 

Where is the power of terrestrial gravitation the greatest? From this point, doe§ 
the power decrease equally, both upwards and downwards? What is the law ol'de- 
erease upwards} Give an example. What is the law «f decrease downward* 
an example. What is the relation between weight and gravity Illustrate it by some 
examples. What, then, is the general law in resrard to the increase and decieaseqf 
attraction ? How may this law be expressed, in the form of a prac ical rule i Suppose, 
for cxamplr. the semi-d/a?neter of the Earth bs estimated, in round numbers, at i00» 
tniUs, aw' that a body, ete.vaiei ZQQQ miles above its surface, should ictigK 40 pound*. 



LAW OF UNIVERSAL GRAVITATION. 269 

Suppose a body weighs 40 pounds at 2000 miles above the Earth's surface, 
what would it weigh at the surface, estimating the Earth's semi-diameter at 
4000 miles 1 From the center to the given height, is If semi-diameters: the 
square of U, or 1.5 is 2.25, which, multiplied into the weight, (40,) gives 90 
pounds, the'answer. 

Suppose a body which weighs 256 pounds upon the surface of the Earth, be 
raised to the distance of the Moon (240,000 miles), what would be its weight? 
Thus, 4000)240,000(60 semi-diameters, the square of which is 3600. As the 
gravity in this case, is decreasing, divide the weight by the square of the dis- 
tance, and it will give 3600)256(l-16th of a pound, or 1 ounce. 

2. To find to what height a given weight must be raised to lose a certain por- 
tion of its weight. 

Rule. — Divide the weight at the surface, by the required weight, and ex- 
tract the square root of the quotient. Ex. A boy weighs 100 pounds, how high 
must he be carried to weigh but 4 pounds? Thus, 100 divided by 4, gives 25, 
the square root of which is 5 semi-diameters, or 20,000 miles above the center. 

Bodies of equal magnitude do not always contain equal 
quantities of matter ; a ball of cork, of equal bulk with one 
of lead, contains less matter, because it is more porous. The 
Sun, though fourteen hundred thousand times larger than 
the Earth, being much less dense, contains a quantity of 
matter only 355,000 times as great, and hence attracts the 
Earth with a force only 355,000 times greater than that with 
which the Earth attracts the Sun. 

The quantity of matter in the Sun is 780 times greater 
than that of all the planets and satellites belonging to the 
Solar System ; consequently their whole united force of at- 
traction is 780 times less upon the Sun, than that of the Sun 
upon them. 

CENTER OF GRAVITY. 




The Center of Gravity of a body, is that point in which 
its whole weight is concentrated, and upon which it would 
rest, if freely suspended. If two weights, one often pounds, 
the other of one pound, be connected together by a rod eleven 
feet long, nicely poised on a center, and then be thrown into 
a free rotary motion, the heaviest will move in a circle with 

tohat would the same body weigh, if brought to the Earth's surface ? Suppose a body 
which xoeighs 256 pounds upon the surface of the Earth, be. raised to the distance of the 
Moon, what xoould be its weight at such an elevation"! [The pupil should be required 
to give the calculation, as well as the answer.] By what rule can we determine tfie 
height to which a body must be raised, in order to its losing a certain portion of its 
weight 7 Give an example. Do bodies of the same magnitude always conViin equal 
quantities of matter? What are the comparative bulks and densities of the Sun and 
Earlh? How great is the quantity of matter in the Sun, compared with that of all the 
planets belonging to the solar system ? What is the center of gravity of a body .' Give 
an example. 



270 LAW OF UNIVERSAL GRAVITATION. 

;i radius of one foot, and the lightest will describe a circle 
with a radius of ten feet: the center around which they 
move is their common center of gravity. See the Figure. 

Thus the Sun and planets move around in an imaginary 
point as a center, always preserving an equilibrium. 

If there were but one body in the universe, provided it 
were of uniform density, the center of it would be the center 
of gravity towards which all the surrounding portions would 
uniformly tend, and they would thereby balance each other. 
Thus the center of gravity, and the body itself, would for- 
ever remain at rest. It would neither move up nor down ; 
there being no other body to draw it in any d:\ection. In 
this case, the terms up and down would have no meaning, 
except as applied to the body itself, to express the direction 
of the surface from the center. 

Were the Earth the only body revolving about the Sun, 
as the Sun's quantity of matter is 355.000 times as great as 
that of the Earth, the Sun would revolve in a circle equal 
only to the three hundred and jifty-Jive thousandth part of 
the Earth's distance from it: but as the planets in their 
several orbits vary their positions, the center of gravity is 
not always at the same distance from the Sun. 

The quantity of matter in the Sun so far exceeds that of 
all the planets together, that were they all on one side of 
him, he would never be more than his own diameter from 
the common center of gravity; the Sun is therefore justly 
considered as the center of the system. 

The quantity of matter in the Earth being about SO times 
as great as that of the Moon, their common center of gravity 
is 80 times nearer the former than the latter, which is about 
3000 miles from the Earth's center. 

The secondary planets are governed by the same laws as 
their primaries, and both together move around a common 
center of gravity. 

Every sysiem in the universe is supposed to revolve in 
like manner, around one common center. 

How does this illustration apply to planetary motion? If there were but one oin-Ie 
body in the universe, where would the center of gravity be? What motion would the 
body hive • What would the terms up and down, in such case, mean? If the Earth 
wee the only body revolving about the Sun, what would be their relative distn. 
their common center of gravity? If, instead of the Earth alone, the Earth with all the 
ptanetsaud satellites of the system were on one side, and the Sun alone on the other. 
at what distance from their common center of gravity must the Sun be, to balance 
them all? Where is the center of gravity between the Earth and the Moon' How 
do you know this? By what laws are the secondary planets governed, and the othe* 
•ysuinas of the universe ? 



ATTRACTIVE AND PROJECTILE FORCES. 271 



ATTRACTIVE AND PROJECTILE FORCES. 

All simple motion is naturally rectilinear; that is, all bo- 
dies put in motion would continue to go forward in straight 
lines, as long as they met with no resistance or diverting 
force. 

On the other hand, the Sun, from his immense size, would, 
by the power of attraction, draw all the planets to him. if his 
attractive force were not counterbalanced by the primitive 
impulse of the planetary bodies to move in straight lines. 

The attractive power of a body drawing another body 
towards the center, is denominated Centripetal farce ; and 
the tendency of a revolving body to fly from the center in 
a tangent line, is called the Projectile or Centrifugal force. 
The joint action of these two central forces gives the planets 
a circular motion, and retains them in their orbits as they 
revolve, the primaries about trie Sun, and the secondaries 
about their primaries. 

The degree of the Sun's attractive power at each particu- 
lar planet, whatever be its distance, is uniformly equal to 
the centrifugal force of the planet. The nearer any planet 
is to the Sun, the more strongly is it attracted by him; the 
farther any planet is from the Sun. the less is it attracted 
by him ; therefore, those planets which are the nearer to 
the Sun. must move the faster in their orbits, in order thereby 
to acquire centrifugal forces equal to the power of the Sun's 
attraction; and those which are the farther from the Sun, 
must move the slower, in order that they may not have too 
great a degree of centrifugal force, for the weaker attraction 
of the Sun at those distances. 

The discovery of these great truths, by Kepler and New- 
ton, established the universal law of flanetary motion ; 
which may be stated as follows: 

1. Every planet moves in its orbit with a velocity varying 
every instant, in consequence of two forces ; one tending to 
the center of the Sun, and the other in the direction of a 
tangent to its orbit, arising from the primitive impulse given 
at the time it was launched into 6pace. The former is called 
its Centripetal, the latter, its Centrifugal force. Should 
the centrifugal force cease, the planet would fall to the Sun 
by its gravity; were the Sun not to attract it. it would fly 
off from its orbit in a straight line. 

What is meant by all simple motion beins rectilinear? Why doe* r.ol the Sun, by 
its great attraction brin? all bodies to its surf.ice? Explain what is meant by centrip- 
etal and centrifugal forces. What results from the joint action of these two forces 1 
To what is the Sun's attractive power at each particular planet equal ? Explain this 
more fully. By wham was the universal law of planetary motion established ! Renea! 
Whe law. 



272 



MOTION OF THE SUN IN SPACE. 



2. By the time a planet has reached its aphelion, or that 
point of its orbit which is farthest from the Sun, his attrac- 
tion has overcome its velocity, and draws it towards him 
with such an accelerated motion, that it at last overcomes 
the Sun's attraction, and shoots past him ; then gradually 
decreasing in velocity, it arrives at the perihelion, when the 
Sun's attraction again prevails. 

MOTION OF THE PLANET3. 




3. However ponderous or light, large or small, near oi 
remote, the planets may be, their motion is always such 
that the radius vector, or line joining its center to the center 
of the Sun, passes over equal areas in equal times : and this 
is true not only with respect to the areas described every 
hour by the same planet, but the agreement holds, with 
rigid exactness, between the areas described in the same 
time, by all the planets and comets belonging to the Solar 
System. 

From the foregoing principles, it follows, that the force of gravity, and the 
centrifugal force, are mutual opposing powers — each continually acting against 
the other. Thus, the weight of bodies on the Earth's equator, is diminithrd 
by the centrifugal force of her diurnal rotation, in the proportion of one pound 
for every 290 pounds : that is, had the Earth no motion on her axis, all bodies 
on the equator would weigh one two hundred arid eighty-ninth part more than 
they now do. 

On the contrary, if her diurnal motion were accelerated, the centrifugal force 
would be proportionally increased, and the weight of bodies at the equator 
would be. in the same ratio, diminished. Should tne Earth revolve upon iw 
axis with a velocity which would make the day but 84 minutes long, instead of 
24 hours, the centrifugal force would counterbalance that of gravity, ami all 
bodies at the equator would then be absolutely destitute of weight ; und if the 

How is the weight of bodies on the Earth's equator affected by its diurnal rotation ! 
What xoould be the. effect if the diurnal motion of the Earth were accelerated > What 
would be the consequtncA if the Earth revolved about its axis in 84 minutes, or in Ust 
timiJ 



MOTION OF THE SUN IN SPACE. 273 

centrifugal force were further augmented (the Earth revolving in less than 81 
minutes), gravitation would be completely overpowered, and all fluids and loose 
substances near the equator would fly off from the surface. 

The weight of bodies, either upon the Earth, or on any other planet having 
a motion arotsnd its axis, depends jointly upon the mass of the planet, and He* 
diurnal velocity. A body weighing one pound upon the equator of ihe Earth, 
would wei«h, if removed to the equator of the Sim, 27.9ibs. ; of Mercury, 1.03 
lbs. : of Venus. 0.98 lbs. ; of the Moon, l-6th of a lb. ; of Mars, £ lb. ; of Jupiter, 
2.716 lbs. ; of Saturn, 1.01 lbs. 



CHAPTER XXL 

PROPER MOTION OF THE SUN IN SPACE. 

Though we are accustomed to speak of the Sun as the 
fixed center of the Solar System, the idea of his fixedness 
is correct only so far as his relation to the bodies revolving 
around him are concerned. As the planets accompanied by 
their satellites revolve around the Sun, so he is found to be 
moving, with all his retinue of worlds, in a vast orbit, around 
some distant and unknown cenier. This opinion was first 
advanced, we think, by Sir William Herschel; but the honor 
of actually determining this interesting fact, belongs to Struve, 
who ascertained not only the direction of the Sun and Solar 
System, but also their velocity. The point of tendency is 
towards the constellation Hercules, Right Ascension 259°. 
Declination 35°. The velocity of the Sun, &c, in space, is 
estimated at about 28,000 miles per hour, or nearly 8 miles 
per second ! 

With this wonderful fact in view, we may no longer con- 
sider the Sun as fixed and stationary, but rather as a vast and 
luminous planet, sustaining the same relation to some cen- 
tral orb, that the primary planets sustain to him, or that the 
secondaries sustain to their primaries. Nor is it necessary 
that the stupendous mechanism of nature should be restricted 
even to these sublime proportions. The Sun's central body 
. may also have its orbit, and its center of attraction and 
motion, and so on. till, as Dr. Dick observes, we come to 
the great center of all — to the Throne of God. 

Since the preceding was written, an article has appeared 
in several European journals, announcing the probable dis- 
covery of the Sun's central orb ; the inclination of his orbit 
to the plane of the ecliptic ; and his periodic time ! 

As it contains several interesting calculations and con- 
clusions, it is here copied for the benefit of the student. 

Is the Sun, Ktrietly speaking, a fixed body ? In what sense is he fixed » What proper 
motion has he? Toward- what point is ho tending ? Who*, is his velocity ? What anal 
ogy, then, between the Sun and fluiiett J 



274 THE CENTRAL SUN. 



THE CENTRAL SUN. 

At the close of the meeting of the Royal Irish Academy 
on the 14th of December, [1846 T ] Sir "William Hamilton 
announced that he had just received from Professor Madler, 
of Dorpat, the extraordinary and exciting intelligence of 
the presumed discovery of a central sun ! 

By an extensive and laborious comparison of the quanti- 
ties and directions of the proper motions of the stars in va- 
rious parts of the heavens, combined with indications afforded 
by the parallaxes hitherto determined, and with the theory 
of universal gravitation, Professor Madler has arrived at the 
conclusion that the Pleiades form the central group of our 
whole astral or sidereal system, including the Milky Way 
and all the brighter stars, but exclusive of the more distant 
nebulae, and of the stars of which those nebula? may be com- 
posed. And within this central group itself he has been led 
to fix on the star Alcyone, (otherwise known by the name 
of J 5 Tauri,) as occupying exactly or nearly the position of 
the center of gravity, and as entitled to be called the central 
sun. 

Assuming Bessel's parallax of the star 61 Cygni, long 
since remarkable for its large proper motion, to be correctly 
determined, Madler proceeds to form a first approximate 
estimate of the distance of this central body from the plane- 
tary or solar system ; and arrives at the (provisional) con- 
clusion, that Alcyone is about thirty-four million times as 
far removed from us, or from our own sun, as the latter lu- 
minary is from us. It would, therefore, according to this 
estimation, be at least a million times as distant as the new 
planet, of which the theoretical or deductive discovery has 
been so great and beautiful a triumph of modern astronomy, 
and so striking a confirmation of the law of Newton. The 
same approximate determination of distance conducts to the 
result, that the light of the central sun occupies more than 
five centuries in traveling thence to us. 

The enormous orbit which our own sun, with the earth 
and the other planets, is thus inferred to be describing about 
that distant center — not indeed under its influence alone, but 
by the combined attractions of all the stars which are nearer 
to it than we are, and which are estimated to amount to 
more than one hundred and seventeen millions of masses, 
each equal to the total mass of our own Solar System — is 

AVhere does Madler locate " The Central Sun? " What star of the group does he de- 
signate as the probable center? How distant does he suppose it to be, as compared 
with Leverrier? How long would it require for light to traverse this space? What is the 
supposed period of the Sun's revolution ? What the inclination of his orbit to the plana 
of the ecliptic? 



PRECESSION OF THE EQUINOXES, &C 275 

supposed to require upwards of eighteen millions of years 
for its complete description, at the rate of about eight geo- 
graphical miles in every second of time. 

The plane of this vast orbit of the sun is judged to have 
an inclination of about eighty-four degrees to the ecliptic, 
or to the plane of the annual orbit of the earth ; and the 
longitude of the ascending node of the former orbit on the 
latter is concluded to be nearly two hundred and thirty-seven 
degrees. 



CHAPTER XXII. 

PRECESSION OF THE EQUINOXES — OBLI- 
QUITY OF THE ECLIPTIC. 

Of all the motions which are going forward in the Solar 
System, there is none, which it is important to notice, more 
difficult to comprehend, or to explain, than what is called 

the PRECESSION OF THE EQ.UINOXES. 

The equinoxes, as we have learned, are the two opposite 
points in the Earth's orbit, where it crosses the equator. 
The first is in Aries; the other, in Libra. By the preces- 
sion of the equinoxes is meant, that the intersection of the 
equator with the ecliptic is not always in the same point: — 
in other words, that the Sun, in its apparent annual course, 
does not cross the equinoctial, Spring and Autumn, exactly 
in the same points, but every year a little behind those of 
the preceding year. 

This annual failing back of the equinoctial points, is called 
by astronomers, with reference to the motion of the heavens, 
the Precession of the Equinoxes ; but it would better accord 
with fact as well as the apprehension of the learner, to call 
it, as it is, the Recession of the Equinoxes: for the equinoc- 
tial points do actually recede upon the ecliptic, at the rate 
of about 50i" of a degree every year. It is the name only, 
and not the position, of the equinoxes which remains per- 
manent. Wherever the Sun crosses the equinoctial in the 
spring, there is the vernal equinox ; and wherever he crosses 
it in the autumn, there is the autumnal equinox, and theso 
points are constantly moving to the west 

What are the equinoxes? What is meant by the pr&zeziinn of the equinoxes I 
Why is it called precession of the equinoxes, and what would he a better term I 
The equinoctial points are conlinuaiiy moving; how.thea i* their po«a« •Jatinefl' 



276 



PRECESSION OF THE EQUINOXES, &C. 




To render this subject fa- 
miliar, we will suppose two 
carriage roads, extending 
quite around the Earth : one, 
representing the equator, 
running due east and west ; 
and the other representing 
the ecliptic, running nearly 
in the same direction as the 
former, yet so as to cross it 
with a small angle (say of 
23i n ), both at the point 
where we now stand, for in- - 
stance, and in the nadir, ex- . 
actly opposite ; let there also 
be another road, to repre- 
sent the prime meridian, 
running north and south. ami 
crossing the first at right 
angles, in the common point 
of intersection, as in the an- 
nexed figure. 

Let a carriage now start 
from this point of inter.-ee- 
tion, not in the road leading 
directly past, but along that of the ecliptic, which leaves the former a little to 
the north, and let a person be placed to watch when the carriage comes aroimd 
again, alter having made the circuit of the Earih. and see whether the carriage 
will cross the equinoctial road again precisely in the same !rr-» as when it left 
the goal. Though the person stood exactly in the former track, he need not 
fear be'ng run over, for the carriage will cross the road 100 rods west of him, 
that is, 100 rods west of the meridian on which he stood It is to oe observed, 
that 100 rods on the equator is equal to 50^ seconds of a deiree. 

If the carriage still continue to go around the Earth, it will, on completing ita 
second circuit, cross the equinoctial path 200 rods west of the meridian whence 
it first set out ; on the third circuit, 300 rods west; on the fourth circuit, 400 
rods, and so on. continually. After 71| circuits, the point of intersection would 
be one degree west of its place at the commencement of the route. At this rate 
it would he easy to determine how many complete circuits the carriage must 
perform before this continual tailing back of the intersecting point would have 
retreated over every degree of the orbit, until it reached again the point (run 
whence it first departed. The application of this illustration will be manifest, 
when we consider, further, that 

The Sun revolves from one equinox to the same equinox 
again, in 365d. 5Ji. 48' 47" .81. This constitutes the natural, 
or tropical year, because, in this perioa. one revolution of 
the seasons is exactly completed. But it is. meanwhile, to 
be borne in mind, that the equinox itself, during this period, 
has not kept its position amo.ig the stars, but has deserted 
its } lace, and Jallen back a little way to meet the Sun; 
whereby the Sun has arrived at the equinox before he hai 
arrived at the same position among the stars from which he 
departed the year before ; and consequently, must perform 
as much more than barely a tropical revolution, to reach 
that point again. 

Give at length a familiar illustration by which this subject may be understood. Su* 
pose the carriage continues its circuit around the Earth, ichere rc-nutd it crov» ;he equi- 
noctial the 'id. 3d. and Ath times, d>c. ? After how many circuits tooutd tnis falling 
bask of the equinoctial -points amount to one degree on the ecl.ptic I In what lime duM 
the Sun revolve from one equinox to the same equinox again ' What is thi-s period 
called Why is i? so .-idled.' Doe* the equinox remain stationary '<as thu period 1 
What leeulU from thu ) 



PRECESSION OF THE EQUINOXES, &C. 



277 



To pass over this interval, which completes the Surfs side- 
real revolution, takes (20' 22".94) about 22 minutes and 23 
seconds longer. By adding 22 minutes and 23 seconds to 
the time of a tropical revolution, we obtain 365d. 6h. 9m.l02s. 
for the length of a sidereal revolution ; or the time in which 
the Sun revolves from one fixed star to the same star again. 

As the Sun describes the whole ecliptic, or 360°, in a trop- 
ical year, he moves over 59' 85" of a degree every day, at a 
mean rate, which is equal to 50?" of a degree in 20 minutes 
and 23 seconds of time ; consequently he will arrive at the 
same equinox or solstice when he is 50?" of a degree, short 
of the same star or fixed point in the heavens, from which 
he set out the year before. So that, with respect to the 
fixed stars, the Sun and equinoctial points fall back, as it 
were, 1° in 7 If years. This will make the stars appear to 
have gone forward 1°, with respect to the signs in the eclip- 
tic, in that time: for it must be observed, that the same signs 
always keep in the, same points of the ecliptic, vnthout re- 
gard to the place of the constellations. Hence it becomes 
necessary to have new plates engraved for celestial globes 
and maps, at least once in 50 years, in order to exhibit truly 
the altered position of the stars. At the present rate of 
motion, the recession of the equinoxes, as it should be called, 
or the precession of the stars, amounts to 30°, or one whole 
sign, in 2 140 years. 



MOTION OF THE STARS. 




To explain this by a figure: Suppose the Sun to have been in conjunction 
with a 6xed star at S. in the first degree of Taurus, (the fecomi si«Ti of the 
ecliptic.) 340 years before the birth of our Saviour, or about the 17th irearef 
Alexander the Great: then having made 2140 revolutions through the e'clip'ic, 
he would be found again at I he end of so many sidereal years at S : but at the 
end of so many Julian year?, he wouid be found at J. and at the end of so 
many Iropiral years, which would bring it down to the beginning of the pre- 
eent century, he would be found at T, in the first degree of Ariesi whim has 
receded fmm S to T in that time by the precession of the equinoctial points 
Aries aud Libra. The arc S T would' be equal to the amount of the precession 

24 



278 PRECESSION OF THE EQUINOXES, &C. 

(for precession we must still call it) of the equinox in 2140 years, at the rate of 
50".23572 of a degree, or 20 minutes and 23 seconds of time annually, as above 
Btated. 

From the constant retrogradation of the equinoctial points, 
and with them of all the signs of the ecliptic, it follows that 
the longitude of the stars must continually increase. The 
same cause affects also their right ascension and declination. 
Hence, those stars which, in the infancy of astronomy were 
in the sign Aries, we now find in Taunts; and those which - 
were in Taurus, we now find in Gemini, and so on. Hence 
likewise it is. that the star which rose or set at any particu- 
lar time of the year, in the time of Hesiod, Eudoxus, Virgil, 
Pliny, and others, by no means answers at this time to their 
descriptions. 

""Hesiod, in his Opera et Dies, lib. ii. verse 185, says: 

When from the solstice sixty wintry days 

Their turns have finished, mark, with glitt'ring rays, 

From Ocean's sacred flood, Arcturus rise, 

Then first to gild the dusky evening skies. 
But Arcturus now rises acronycallyin latitude 37° 45' N. the latitude of He- 
siod, and nearly that of Richmond, in Virginia, about 100 days after the winter 
solstice. Supposing Hesiod to be correct, there is a difference of 40 days arising 
from the precession of the equinoxes since the days of Hesiod. Now as there 
is no record extant of the exact period of the world when this poet flourished, 
let us see to what result astronomy will lead us. 

As the Sun moves through about 39° of the ecliptic in 40 days, the winter sol- 
stice, in the time of Hesiod, was in the 9th degree of Aquarius. Now estimat- 
ing the precession of the equinoxes at 50j" in a year, we shall have 50}" : 1 
year: : 39° : 2794 years since the time of Hesiod: if we substract from this 
our present era, 1S36, it will give 953 years.before Christ. Lempriere, in his 
Classical Dictionary, says Hesiod lived 907 years before Christ. See a similar 
calculation for the time of Thales, page 54. 

The retrograde movement of the equinoxes, and the an- 
nual extent of it, were determined by comparing the longi- 
tude of the same stars, at different intervals of time. The 
most careful and unwearied attention was requisite in order 
to determine the cause and extent of this motion ; a motion 
so very slow as scarcely to be perceived in an age, and oc- 
cupying not less than 25,000 years in a single revolution. 
It has not yet completed one quarter of its frst circuit in 
the heavens since the creation. 

Thus observation has not only determined the absolute 

How long does it take the Sun (o pass over the interval of space through which 
the equinox has thus retreated ' What is the length of a sidereal revolution, and 
how is it determined ? What portion of the ecliptic does the Sun describe, nt a mean 
rate, every day "What portion does it desciibe in £0 minutes and 23 seconds ' II the 
Sun and equinoctial points fall hack in the ecliptic 50 1-4'' of a degree every year, how 
many years before this regression will amount to a degree How will tins alieel the 
appearance of the stars? What practical inconvenience results Horn this fact) In what 
period of time does the precession of the stars amount to 30°, or one whi 
Explain this by a diagram. How does the retrogradation of the equinoctial points 
affect the longitude of the .-tars? Docs the same cau-e extend to the right . 
and declination also? How is this rendered ai i arent Mention an 
does not enable us to jix lite precise cge of the loorld in w'tch I 
what light dons astronomy shed upon this question ■ By what means was the retro- 
gradation of the equinoxes determined ? Wh\ was it difficult to determine the came 
and extent of this motion paiticular cases, what has observation at 

length determined, with respect to the Hunt and uniformity of this backward move- 
ment of the equinoctial | i 



PRECESSION OF THE EQUINOXES, &C. 279 

motion of the equinoctial points, but measured its limit; it 
has also shown that this motion, like the causes which pro- 
duce it, is not uniform in itself: but that it is constantly ac- 
celerated by a slow arithmetical increase of 1" of a degree 
in 4,100 years. A quantity which, though totally inappre- 
ciable for short periods of time, becomes sensible after a 
lapse of ages. For example : The retrogradation of the 
equinoctial points is now greater by nearly i" than it was 
in the time of Hipparchus, the first who observed this mo- 
tion ; consequently, the mean tropical year is shorter now 
by about 12 seconds than it was then. For, since ihe retro- 
gradation of the equinoxes is now every year greater than 
it was then, the Sun has, each year, a space of nearly k 1 ' 
less to pass through in the ecliptic, in order to reach the 
plane of the equator. Now the Sun is 12 seconds of time in 
passing over \" of space. 

At present, the equinoctial points move backwards, or 
from east to west along the path of the ecliptic at the rate 
of 1° in 71# years, or one whole sign, in 2 J 40 years. Con- 
tinuing at this rate, they will fall back through the whole 
of the 12 signs of the ecliptic in 25.6S0 years, and thus return 
to the same position among the stars, as in the beginning. 

But in determining the period of a complete revolution of 
the equinoctial points, it must be borne in mind that the 
motion itself is continually increasing ; so that the last quar- 
ter of the revolution is accomplished several hundred years 
sooner than the first quarter. Making due allowance for this 
accelerated progress, the revolution of the equinoxes is com- 
pleted in 25,000 years ; or, more exactly, in 24.992 years. 

Were the motion of the equinoctial points uniform ; that 
is, did they pass through equal portions of the ecliptic in 
equal times, they would accomplish their first quarter, or pass 
through the first three signs of the ecliptic, in 6,250 years. 
But they are 6,575 years in passing through the first quar- 
ter; about 218 years less in passing through the second 
quarter; 218 less in passing through the third, and so on; 

The immediate consequence of the precession of the equi 
noxes, as we have already observed, is a continually pro- 
gressive increase of longitude in all the heavenly bodies. 
For the vernal equinox being the initial point of longitude, 

Give an example. Why should the tropical year, on this account, be shorter now 
than it was then? What is the present rate of motion of the equinoctial points? 
In what time, continuing at the same rate, will they fall back through the twelve signs 
of the ecliptic? In determining the exact period of a complete revolution of the equi- 
noctial points, what important circumstance must be borne in mind? Making due 
allowance for their accelerated progress, in what tin ">e is a revolution of the equinoxes 
completed? Is this motion as quick in the first quarter of their revolution as in the last? 
What is the time and difference of describing each quaner? What is the immediate 
consequence of the preressiwn of the equinoxes upon the position of the heavenly bo- 
dies? Explain how this takes place. How does this resemble the annual Loss of a 
•idereal day by the Sun ? What is the cause of this motion ? 



280 PRECESSION OF THE EQUINOXES, &C. 

as well as of right ascension, a retreat of this point on the 
ecliptic, tells upon the longitudes of all alike, whether at rest 
or in motion, and produces, so far as its amount extends, the 
appearance of a motion in longitude common to them all, 
as if the whole heavens had a slow rotation around the poles 
of the ecliptic in the long period above mentioned, similar to 
what they have in every twenty-four hours around the poles 
of the equinoctial. As the Sun loses one day in the year 
on the stars, by his direct motion in longitude ; so the equi- 
nox gains one day on them, in 25,000 years, by its retro- 
grade motion. 

The cause of this motion was unknown, until Newton 
proved that it was a necessary consequence of the roiation 
of the Earth, combined with its elliptical figure, and the 
unequal attraction of the Sun and Moon on its polar and 
equatorial regions. There being more matter about the 
Earth's equator than at the poles, the former is more strongly 
attracted than the latter, which causes a slight gyratory or 
wabbling motion of the poles of the Earth around those of 
the ecliptic, like the pin of a top about its center of motion, 
when it spins a little ribliquely to the base. 

The precession of the equinoxes, thus explained, consists 
in a real motion of the pole of the heavens among the stars, 
in a small circle around the pole of the ecliptic as a center, 
keeping constantly at its present distance of nearly 23i° 
from it, in a direction from east to west, and with a progress 
so very slow, as to require 25.000 years to complete the cir- 
cle. During this revolution, it is evident that the pole will 
point successively to every part of the small circle in the 
heavens which it thus describes. Now this can not happen 
without producing corresponding changes in the apparent 
diurnal motion of the sphere, and in the aspect which the 
heavens must present at remote periods of time. 

The effect of such a motion on the aspect of the heavens, 
is seen in the apparent approach of some stars and constel- 
lations to the celestial pole, and the recession of others. 
The bright star of the Lesser Bear, which we call the pole 
star, has not always been, nor will always continue to be, 
our polar star. At the time of the construction of the earliest 
catalogues, this star was 12° from the pole ; it is now only 
1° 34' from it. and it will approach to within half a degree 
of it; after which it will again recede, and slowly give place 
to others, which will succeed it in its proximity to the pole. 

Admitting this explanation, in what does the precession of the equinoxes really con- 
sist? To what point in the heavens will the pole of ihe Earth be directed, during the 
revolution ? How must this affect the diurnal motion and aspect of the heav, 
mote ages? 'Wherein will the effects of such a motion be iKirUcularly visible? Give 
an instance . 



PRECESSION OF THE EQUINOXES, &C. 281 

The pole, as above considered, is to be understood, merely, as the vanishing 
point of the Earth's axis; or that point in the concave sphere which is always 
opposite the terrestrial pole, and which consequently must mcwe as that moves. 

The precession of the stars in respect to the equinoxes, is 
less apparent the greater their distance from the ecliptic ; 
for whereas a star in the zodiac will appear to sweep the 
whole circumference of the heavens in an equinoctial year, 
a star situated within the polar circle will describe only a 
very small circle in that period, and by so much the less, as 
it approaches the pole. The north pole of the earth being 
elevated 23° 27§' towards the tropic of Cancer, the circum- 
polar stars will be successively at the least distance from it, 
when their longitude is 3 signs, or 90° The position of the 
north polar star in 1836, was in the 17° of Taurus ; when 
it arrives at the first degree of Cancer, which it will do in 
about 250 years, it will be at its nearest possible approach 
to the pole — namely, 29' 55". About 2900 years before 
the commencement of the Christian era, Alpha Draconis, 
the third star in the Dragon's tail, was in the first degree of 
Cancer, and only 10' from the pole ; consequently it was 
then the pole star. After the lapse of 11,600 years, the star 
Lyra, the brightest in the northern hemisphere, will occa- 
py the position of a pole star, being then about 5 degrees 
from the pole ; whereas now its north polar distance is up- 
wards of 51°. 

The mean average precession from the creation (4004 B. C.) to the year 1800, 
is 49".51455 ; consequently the equinoctial points have receded since the creation, 
2 s. 14° 8' 27". The longitude of the star Beta Arietis, was. in 1820, 31° 27' 28" : 
Melon, a famous mathematician of Athens, who flourished 430 years before Christ, 
says, this star, in his time, was in the vernal equinox. If he is correct, then 
31° 27' 28", divided by 2250 years, the elapsed time, will give 50f w for the preces- 
sion. Something, however, must be allowed for the imperfection of the instru- 
ments used at that day, and even until the sixteenth century. 

Since all the stars complete half a revolution about the 
axis of the ecliptic in about 12,500 years, if the North Star 
be at its nearest approach to the pole 250 years hence, it 
will, 12,500 years afterwards, be at its greatest possible dis- 
tance from it, or about 47° above it : — That is, the star itself 
will remain immovable in its present position, but the pole 
of the Earth will then point as much below the pole of the 
ecliptic, as now it points above. This will have the effect, 

When you speak of the POLE as in motion, what is to be understood by that tervxi 
Is the precession of the stars, with respect to the equinoxes, equally apparent in every 
part of the heavens? At what longitude do the circumpolar stars approach nearest the 
j.iole? AVhat is the position, at present, of the north polar star, and when will it make 
its nearest possible approach to the true pole of the heavens? At what period has any 
other star been the polar star ? "When will the star Lyra, which is more than 5(P from 
it, be the north polar star } What loas the mean annua/ precession from the creation 
to the year 1800, and how much did it amount to in that period? When was Beta Ari- 
etis in the equinox, and what is its longitude now ? "When will our present north star 
be at its least, and when at its greatest distance from the pole ? In this case, is it meant 
that the star itself will move, or the pole? In what manner? What, then, must be the 
apparent effect ? 

24* 



282 OBLIQUITY OF THE ECLIPTIC. 

apparently, of elevating the present polar star to twice its 
present altitude, or 47°. Wherefore, at the expiration of 
half the equinoctial year, that point of the heavens which is 
now 1° IS' north of the zenith of Hartford, will be the place 
of the north pole, and all those places which are situated 1° 
18' north of Hartford, will then have the present pole of the 
heavens in their zenith. 

OBLIQUITY OF THE ECLIPTIC. 

The distance between the equinoctial and either tropic, 
measured on the meridian, is called the Obliquity of the 
Ecliptic : or, this obliquity may be defined as the angle 
formed by the intersection of the celestial equator with the 
ecliptic. Hitherto, we have considered these great primary 
circles in the heavens, as never varying their position in 
space, nor with respect to each other. But it is a remarkable 
and well-ascertained fact, that both are in a state of constant 
change. We have seen that the plane of the Earth's equa- 
tor is constantly drawn out of place by the unequal attraction 
of the Sun and Moon acting in different directions upon the 
unequal masses of matter at the equator and the poles; 
whereby the intersection of the equator with the ecliptic is 
constantly retrograding — thus producing the precession of 
the equinoxes. 

The displacement of the ecliptic, on the contrary, is pro- 
duced chiefly by the action of the planets, particularly of 
Jupiter and Venus, on the Earth; by virtue of which the 
plane of the Earth's orbit is drawn nearer to those of these 
two planets, and consequently, nearer to the plane of the 
equinoctial. The tendency of this attraction of the planets, 
therefore, is to diminish the angle which the plane of the 
equator makes with that of the ecliptic, bringing the two 
planes nearer together ; and if the Earth had no motion of 
rotation, it would, in time, cause the two planes to coincide. 
But in consequence of the rotary motion of the Earth, the 
inclination of these planes to each other remains very nearly 
the same; its annual diminution being scarcely more than 
three fourths of one second of a degree in a year. 

The obliquity of the ecliptic, at the commencement of the present century, 
was, according to Baily, 23° 27' 56A". subject to a yearly diminution of i 
According to Bessel, it was 23^ 27' 54" .32, with an annual diminution of 0" .46. 

Ulustraie. these, phenomena by a diagram. What is the obliquity of the ecliptic? 
In what light have we hitherto considered the sreat circles of the heavens? But what 
is the fact? By what cause is the displacement of the equinoctial, or the plane of the 
Earth's equator, effected > How is the displacement of the plane of the ecliptic effect 
ed 1 If the planetary attraction tends constantly to draw the planes of the equinoctial 
and ecliptic nearer together, wh it is to prevent them from coinciding .*n one h\a\ the 
same plane ? How much if the distance oran<rle between th<*m diminished ei 
What ?>w» the. obliquity of the ecliptic, or the quantity of this tingle, at the commence- 
ment of th e present century ? la the annual diminution of tfie obliquity subject to ant 
variation ? 



OBLIQUITY OF THE ECLIPTIC. 283 

This diminution, however, is subject to a slizht semi-annual variation, from the 
game causes which produce the displacement of the plane of the ecliptic, in 
precession. 

The attraction of the Sun and Moon, also, unites with that 
of the planets, at certain seasons, to augment the diminution 
of the obliquity, and at other times, to lessen it. On this 
account the obliquity itself is subject to a periodical varia- 
tion ; for the attractive power of the Moon, which tends to 
produce a change in the obliquity of the ecliptic, is variable, 
while the diurnal motion of the Earth, which tends to pre- 
vent the change from taking place, is constant. Hence the 
Earth, which is so nicely poised on her center, bcncs a little 
to the influence of the Moon, and rises again, alternately, 
like the gentle oscillations of a balance. This curious phe- 
nomenon, is called Nutation. 

In consequence of the yearly diminution of the obliquity 
of the ecliptic, the tropics are slowly and steadily approach- 
ing the equinoctial, at the rate of little more than three 
fourths of a second every year; so that the Sun does not 
now come so far north of the equator in summer, nor decline 
bo far south in winter, by nearly a degree, as it must have 
done at the creation. 

The most obvious effect of this diminution of the obliquity 
of the ecliptic, is to equalize the length of our days and 
nights ; but it has an effect also to change the position of 
the stars near the tropics. Those which were formerly 
situated north of the ecliptic, near the summer solstice, are 
now found to be still farther north, and farther from the 
plane of the ecliptic. On the contrary, those which, accord- 
ing to the testimony of the ancient astronomers, were situ- 
ated south of the ecliptic, near the summer solstice, have 
approached this plane, insomuch that some are now either 
situated within it, or just on the north side of it. Similar 
changes have taken place with respect to those stars situ- 
ated near the winter solstice. Ail the stars, indeed, partici- 
pate more or less in this motion, but less, in proportion to 
their proximity to the equinoctial. 

It is important, however, to observe, that this diminution 
will not always continue. A time will arrive when this 
motion, growing less and less, will at length entirely cease, 
and the obliquity will, apparently, remain constant for a 
time ; after which it will gradually increase again, and con- 

' From xchat caiue l What effect has the attraction of the Sun and Moon on this ob- 
liquity ? What results from this alternate and opposite influence? By what token doe9 
the Earth show respect to this influence of the .Moon ? What is this phenomenon called ? 
What is the consequence of the yearly diminution of the obliquity of the ecliptic in re- 
spect to the position of the tropics, and the declination of the Sun ? What other obvi- 
ous effects result from this diminution ? How does it affect the declination of the sura 
near the solstices > Do all the stars partake, more or lc*» in this motion.' Will thia 
diminution of the obliquity always continue ! 



284 



THE TJDES. 



tinue to diverge by the same yearly increment as it before 
had diminished. This alternate decrease and increase will 
constitute an endless oscillation, comprehended between cer- 
tain fixed limits. Theory has not yet enabled us to deter- 
mine precisely what these limits are, but it may be demon- 
strated from the constitution of our globe, that such limits 
exist, and that they are very restricted, probably not exceed- 
ing 2° 42'. If we consider the effect of this ever-varying 
attribute in the system of the universe, it may be affirmed 
that the plane of the ecliptic never has coincided with the 
plane of the equator, and never will coincide with it. Such 
a coincidence, could it happen, would produce upon the 
Earth perpetual spring. 

The method used by astronomers to determine the obli- 
quity of the ecliptic is, to take half the difference of the 
greatest and least meridian altitudes of the Sun. 

The following table exhibits the mean obliquity of the 
ecliptic for every ten years during the present century. 



1800 


23° 27' 54" 


.78 


1860 


23° 27' 27" 


.36 


1810 


23 27 50 


.21 


1870 


23 27 22 


.79 


1820 


2? 27 45 


.64 


1880 


23 27 18 


.22 


1830 


23 27 41 


.07 


1890 


23 27 13 


.65 


1840 


23 27 36 


.50 


1900 


23 27 09 


.08 


1850 


23 27 31 


.93 


1910 


23 27 04 


.52 



CHAPTER XXIII. 



THE TIDES. 

The oceans, and all the seas, are observed to be incessant- 
ly agitated for certain periods of time, first from the east 
towards the west, and then again from the west towards the 
east. In this motion, which lasts about six hours, the sea 
gradually swells ; so that entering the mouth of rivers, it 
drives back the waters towards their source. After a con- 
tinual flow of six hours, the seas seem to rest for about a 
quarter of an hour ; they then begin to ebb, or retire back 
again from west to east for six hours more ; and the rivers 
again resume their natural courses. Then after a seeming 
pause of a quarter of an hour, the seas again begin to flow, 
as before, and thus alternately. This regular alternate mo- 

What are the limits of its alternate variation ? What would be the consequence, in 
respect lothe seasons, should the plane of the ecliptic ever coincide with ihe plane of 
the equator? What is the method used by astronomers for determining the obliquity of 
the ecliptic? What regular motion is observed in the gieat body of waters upon the 
globe > In what periods of time is this alternate ebbing and flowing accomplished ? 



THE TIDES. 285 

tion of the sea constitutes the tides, of which there are two in 
something less than twenty-five houi s. 

The ancients considered the ebbing and flowing of the tides as one of the 
greatest mysteries in nature, and were utterly at a loss to account for them. 
Galileo and Descartes, and particularly Kepler, made some successful advances 
towards ascertaining the cause ; but Sir Isaac Newton was the first who 
clearly showed what were the chief agents in producing these motions. 

The cause of the tides, is the attraction of the Sun and 
Moon, but chiefly of the Moon, upon the waters of the 
ocean. In virtue of gravitation, the Moon, by her attrac- 
tion, draws, or raises the water towards her ; but because 
the power of attraction diminishes as the squares of the dis- 
tance increase, the waters on the opposite side of the Earth 
are not so much attracted as they are on the side nearest 
the Moon. 

That the Moon, says Sir John Herschel, should, by her attraction, heap up 
the waters of the ocean under her, seems to most persons very natural ; but 
that the same cause, should, at the same time, heap them up on the opposite 
side, seems, to many, palpably absurd. Yet nothing is more true, nor indeed 
more evident, when we consider that it is not by her whole attraction, but by 
the differences of her attractions at the opposite surfaces and at the center, that 
the waters are raised. 

That the tides are dependent upon some known and determinate laws, is evi- 
dent from the exact time of high water being previously given in every ephe- 
meris. and in many of the common almanacs. 

The Moon comes every day later to the meridian than on the day preceding, 
and her exact time is known by calculation ; and the tides in any and every 
place, will be found to follow the same rule ; happening exactly so'much later 
every day as the Moon comes later to the meridian. From this exact conform- 
ity to the motions of the Moon, we are induced to look to her as the cause ; and to 
infer that these phenomena are occasioned principally by the Moon's attraction. 

CAUSE OF THE TIDES. 






If the Earth were at rest, and there were no attractive in- 
fluence from either the Sun or Moon, it is obvious from the 
principles of gravitation, that the waters in the ocean would 
be truly spherical, as represented at A ; but daily observation 
proves that they are in a state of continual agitation. 

What is it called ? How were these phenomena regarded by the ancients i Who 
ascertained their true cause ? What is the cause of the tides ? How does the attraction 
of the Sun and Moon produce tides upon both sides of the Earth at the same time? 
iv hat is Sir John Hersdieis remark upon this theory ? Hoic it it known that the tide* 
are governed by any ascertained lata 1 What coincidence is observed between the me- 
ridian passage of the Moon, and the rime of high water i What conclusion may we de- 
rive from this coincidence ? If the Earth were at rest, and under no influence from th* 
attraction ot the Sun or Moon, what sh.ipe would the wateri assume? 



286 THE TIDES. 

If the Earth and Moon were without motion, and the 
Earth covered all over with water, the attraction of the Moon 
would raise it up in a heap, in that part of the ocean under 
the Moon, as represented at B, and there it would, probably, 
always continue ; but by the rotation of the Earth upon its 
axis, each part of its surface to which the Moon is vertical 
is presented to the action of the Moon ; wherefore, as ihe 
quantity of water on the whole Earth remains the same, 
when the waters are elevated on the side of the Earth under 
the Moon, and on the opposite side also, it is evident they 
must recede from the intermediate points, and thus the at- 
traction of the Moon produce high water at two opposite 
places, and low water at two opposite places, on the Earth, 
at the same time. 

This is evident from the following figure. The waters cannot rise in one 
place without falling in another ; and therefore they must fall as low in the hor- 
izon, ar C and D, as they rise in the zenith and nadir, at A and B. 





It has already been shown, under the article gravitation 
that the Earth and Moon would fall towards each other, by 
the power of their mutual attraction, if there were no centri- 
fugal force to prevent them ; and that the Moon would fall 
as much faster towards the Earth than the Earth would fall 
towards the Moon, as the quantity of matter in the Earth is 
greater than the quantity of matter in the Moon. The same 
law determines also the size of their respective orbits around 
their common center of gravity. 

It follows then, as we have seen, that the Moon does not revolve, strictly 
speaking, around the Earth as a center, but around a point beticeen them, 

Suppose the attractive power of the Moon upon the Earth to oe as it is, and neitheT 
the Earth nor Moon to have any motion, what would be the result? How would this 
condition of things be affected by the Earth's rotation? If the Earth and Moon mu- 
tually attract each other with so much force, what prevents their coming together ? But 
centrifugal force results only from circular motion, does the Earth then circulate around 
the Moon to acquire the centrifugal force by which it is kept from falling upon the 
Moon? [Ans. The Earth does not circulate around the Moon, hut around the com- 
mon center of gravity between it and the Moon] Where is this center situated, and 
in what time does the Earth revolve about it > [Ans. The center of gravity, between 
the Earth and the Moon, is about 3000 miles from the Earth's center, around which it 
revolves every lunar month, or as often as the Moon revolves around the Earth] Frtmi 
the fact of the Earth's motion, as in the case described, hoir do srmw. philosophers ac- 
count for high water on the side of the Earth, opposite to the Moon ? How is thii 
phenomenon otherwise explained, by the laws of gravity, merely? Are the Earthand 
waters of the globe affected equally, by the Moon's attraction ? Why not! 



THE TIDES. 287 

which is 80 times nearer the Earth than the Moon, and consequently is situated 
About 3000 miles from the Earth's center. It has also been shown, that all 
bodies moving in circles acquire a centrifugal force proportioned to their re- 
spective masses and velocity. From these facts, some philosophers account 
for high water on the side of the Earth opposite to the Moon, in the following 
manner :— 
As the Earth and Moon move around their common center of gravity, that 

fart of the Earth which is at any time turned from the Moon, being about 
000 miles farther from the center of gravity, than the side next the Moon, would 
have a greater centrifugal force than the side next her. At the Earth's cen- 
ter, the centrifugal force will balance the attractive force ; therefore as much 
water is thrown off by the centrifugal force on the side which is turned from 
the Moon, as is raised on the side next her by her attraction. 

From the universal law, that the force of gravity dimin- 
ishes as the square of the distance increases, it results, that 
the attractive power of the Moon decreases in intensity at 
every step of the descent from the zenith to the nadir ; and 
consequently that the waters on the zen«ith, being more 
attracted by the Moon than the Earth is at its center, move 
faster towards the Moon than the Earth's center does : and 
as the een er of the Earth moves faster towards the Moon 
than the waters about the nadir do, the waters will be, as it 
were, left behind, and thus, with respect to the center, they 
will be raised. 

The reason why the Earth and waters of our globe do not seem to be affected 
equally by the Moon's attraction, is, that the earthy substance of the globe, 
being firmly united, does not yield to any difference of the Moon's attractive 
force; insomuch that its upper and lower surface must move equally fast 
towards the Moon ; whereas the waters, cohering together but very lightly, 
yield to the different degrees of the Moon's attractive force, at different dis- 
tances from her. 

The length of a lunar day, that is, of the interval from 
one meridian passage of the Moon to another, being, at a 
mean rate, 24 hours, 48 minutes and 44 seconds, the inter- 
val between the flux and the reflux of the sea is not, at a 
mean rate, precisely six hours, but twelve minutes and 
eleven seconds more, so that the time of high water does 
not happen at the same hour, but is about 49 minutes later 
every day. 

The Earth revolves on its axis in about twenty-four hours ; 
if the Moon, therefore, were stationary, the same part of our 
globe would return beneath it, and there would be two tides 
every twenty-four hours; but while the Earth is turning once 
upon its axis, the Moon has gone forward 13° in her orbit — 
which takes forty-nine minutes more before the same meri- 
dian is brought again directly under the Moon. And hence 
every succeeding day the time of high water will be forty- 
nine minutes later than the preceding. 

For example :— Suppose at any place it be high water at 3 o'clock in the af- 
ternoon, upon the day of new Moon, the following day it will fee high water 
about 49 minutes after 3 ; the day after, about 33 minutes after 4 ; and so on till 

What is the average interval between the flux and reflux of the sea? V*J in tb« 
ength of a lunar day, and of the interval of the flux and reflux ofthe»c, U;i v 
4ii* daily retardation of the hues accounted for ; (Jive an cxamplt. 



288 



THE TIDES. 



the next Hew Moon. The exact daily mean retardation of the tides is thua 

determined : — 
The mean motion of the Moon, in a solar day, is 13°. 17639639 
The mean .motion of the Sun, in a 6olar day, (a .9S564722 



Now, as 15° is t0 60 minutes, so is 12M9074917 to 4S' 44". 

It is obvious that the attraction of the. Sun must produce 
upon the waters of the ocean a like effect to that of the 
Moon, though in a less degree ; for the great mass of the 
Sun is more than compensated by its immense distance. 
Nevertheless, its effect is considerable, and it can be shown, 
that the height of the solar tide is to the height of the lunar 
tide as 2 to 5. Hence the tides, though constant, are not 
equal. They are greatest when the Moon is in conjunction 
with, or in opposition to. the Sun, and least when in quad- 
rature. For in the former case, the Sun and Moon set to- 
gether, and the tide will equal the sum of the solar and lunar 
tides, and in the latter they act against each other, and the 
tide will be the difference. 

The former are called Spring Tides; the latter, Neap 
Tides. 

SPRING AND NEAP TIDES. 




Are the tides uniformly high? When, and on what aeeount, do they differ? What 
are these extreme tides called ? When an the spring tides highest > When are the 
neap tides lowest? 



THE TIDES. 289 

The spring tides are highest, when the Sun and Moon 
are near the equator, and the Moon at her least distance 
from the Earth. The neap tides are lowest, w T hen the Moon 
in her first and second quarters is at her greatest distance 
from the Earth. The general theory of the tides is this j 
When the Moon is nearest the Earth, her attraction is 
strongest, and the tides are the highest ; when she is i'arthest 
from the Earth, her attraction is least, and the tides are the 
lowest. 

From the above theory, it might be supposed that the tides 
would be the highest when the Moon was on the meridian. 
But it is found that in open seas, where the water flows 
freely, the Moon has generally passed the north or south 
meridian about three hours, when it is high water. This is 
called the 

LAGGING OF THE TIDES IN LONGITUDE. 




This lagging of the tide behind the Moon is illustrated by 
the above cut, in which the Moon is seen on the meridian, 
and the vertex of the tide-wave A, about three hours, or 
22i° east of that meridian. The opposite wave is also in 
its corresponding position, as shown at B. 

The reason of this delay of the tide is, that the force by 
which the Moon raises the tide continues to act, and conse- 
quently the waters continue to rise, after she has passed the 
meridian. 

For the same reason, the highest tides, which are pro 
duced by the conjunction and opposition of the Sun and 
Moon, do not happen on the days of the full and change ; 
neither do the lowest tides happen on the days of their 
quadratures. But the greatest spring tides commonly hap- 
pen li days after the new and full Moons ; and the least 
neap tides \h days after the first and third quarters. 

What ia the general theory UDon this subject? Does it necessarily result from thii 
theory, that the tide is highest when the Moon is on the meridian ' What remon t» 
assigned for this > What similar tuct is uecouattd tor u; on the same principle • 



290 



THE TIDES! 



The Son and Moon, by reason of the elliptical form of their orbits, are alter- 
ratelv nearer to and farther from the Earth, than their mean distances. In 
consequence of this, the efficacy of the Sua will fluctuate »'^ween the extremes 
19 and 21, taking 20 for its mean value, and between 43 and 59 ioi thai ot the 
Moon Takin- into account this cause of difference, the highest spring tide 
w 11 be tolhe lowest neap as 59+21 is to 43-19, or as 80 to 24. or 10 to 3. The 
relative mean influence is as 51 to 20, or as 5 to 2. nearly. -HeracheMAftr. 
p. 339. 

The cause of this variation of the tides is illustrated in the 
following cut, in which the Earth and Moon are both shown 
as revolving in elliptical orbits. 



// 



% 



!■€ 



&■ 




^\» 




Vy 3y 



& 



// 



Kt B both the Earth and Moon are in Perigee, conse- 
quently the Sun and Moon will both exert their greatest 
attractive influence upon the Earth, and there will be the 
highest possible tide. 

At A the Earth and Moon are in Apogee, and though the 
Sun and Moon are in conjunction, and unite their attractive 
forces the same as at B. to produce a spring tide, yet. as 
thevare both at their greatest distance from the Earth, they 
exert their least possible influence, and the result is a mod- 
erate spring tide, as shown in the figure. 

Though the tides, in open seas, are at the highest aboui 
three hours after the Moon has passed the meridian, yet the 
waters in their passage through shoals and channels, and by 
slrikino- against capes and headlands, are so retarded I hat 
to different places, the tides happen at all distances ot the! 
Moon from the meridian; consequently at all hours ol the 
lunar day. 

EXCURSION OF THE TIDES IN LATITUDE. 

The vertices of the tide-wave are subject to r 
latitude, owing to the changes in the position of the San aim 



What fc the comparative/™ of the - ar and lunar atirar.t.on y°"J^'"'L *? 
what is owing the prcat ,lirtVr.-n.-e m the nm« ot h,,h water at Hares bins under the 
same meridian? What is meant by the Sun's declination^ by what is it caused? 



THE TIDES. 



291 



Moon, as respects the equator. The inclination of the 
Earth's axis to the ecliptic, and her revolution around the. Sun, 
cause him to appear to oscillate north and south from tropic 
to tropic once and back every year. 'This is what is called 
his declination. It is northern or southern, according as he 
is north or south of the equator, and is reckoned in degrees 
from that point. Of course it can never exceed 23° 28," th& 
amount of the polar inclination to the ecliptic. 

But at the same time that the Sun appears to move, first 
north and then south of the equator, it is evident that Tie still 
remains in the ecliptic, from which the Moon next departs 
more than 5° 9". Whenever, therefore, the Sun- has great 
Southern declination, as, for instance, at the time of the winter 
solstice, the Moon also must be far south at the time of her 
conjunction with him, or at new Moon ; .and as both these- 
causes of the tides are south of the equator, the vertex of 
the tide-wave just east of their meridian will be in the 
southern hemisphere, and the one on the opposite side of 
the Earth in the northern hemisphere. 

In the following diagram the excursion of the tide-wave 
in latitude, is represented to the eye. 




Let the line A A represent the plane of the ecliptic, B B 
the equinoctial, or plane of the Earth's equator, &c. On the 
21st. of June the Sun is vertical over the Northei^n tropic, and 
at new Moon the highest tide-wave in the northern hemi- 
sphere will be ahout three hours after the Sun crosses the 
meridian. At the same time the opposite wave will be in 
the southern hemisphere, as shown at C. 

On the 23d of Sept. the Sun and Moon are far south at 
conjunction; the tide-wave following them is highest in the 
southern hemisphere, and the opposite wave smaller over 
the northern. If. then, the southern vertex be three hours be- 
hind the Sun. as shown on page 289, or comes to the meridi- 
an at 3 o'clock P. M., the opposite wave which is twelve 



What is its jrreatest extent? Is (he Sun still in the ecliptic when 23 a 28" from the 
equinoctial.) How Car (tin the Moon depart from the ecliptic' Where must tho 
IWoon be. then, at conjunction, when the Sun has great southern declination ! AVhat 
effect does this have upon the tides? At what time do we have the highest tides at 
the north in summer ? When, in winter ) 



292 THE TIDES. 

hours behind it, must come to the same meridian about 
3 o'clock in the morning. It is on this account, that in high 
latitudes every alternate tide is higher than the interme- 
diate ones, the evening tides in summer exceeding the 
morning tides, and the morning tides in winter exceeding 
those of the evening. 

TIDES IN INLAND SEAS, LAKES, ETC. 

In small collections of water, the Moon acts at the same 
lime on every part, diminishing the gravity of the whole 
mass. On this account there are no sensible tides in lakes, 
they being generally so small that when the Moon is verti- 
cal, it attracts every part alike j and by rendering all the 
waters equally light, no part of them can be raised higher 
than another. The Mediterranean and Baltic seas have 
very small elevations, partly for this reason, and partly be- 
cause the inlets by which they communicate with the ocean 
are so narrow, that they cannot, in so short a time, either 
receive or discharge enough, sensibly to raise or sink their 
surfaces. 

Of all the causes of difference in the height of tides at 
different places, by far the greatest is local situation. In 
wide-mouthed rivers, opening in the direction of the stream 
of the tides, and whose channels are growing gradually 
narrower, the water is accumulated by the contracting 
banks, until in some instances it rises to the height of 20, 30, 
and even 50 feet. 

ATMOSPHERICAL TIDES. 

Air being lighter than water, and the surface of the at- 
mosphere being nearer to the Moon than the surface of the 
•sea, it cannot be doubted but that the Moon raises uracil 
higher tides in the atmosphere than in the sea. According 
to Sir John Herschel these tides are, by very delicate obser- 
vations, rendered not only sensible, but measurable. 

Upon the supposition that there is water on the surface of the Moon of the 
same specific gravity as our own, we might easily determine the height to 
which the Earth would raise a lunar tide, by the known principle, thai the at- 
traction of one of these bodies on the other's surface is directly as its quantity 
of matter, and inversely as its diameter. By making the calculation, we shall 
find the attractive power of the Earth upon the Moon to be 21.777 times greater 
than that of the Moon upon the Earth. 

Why are there no rides upon lakes, and small collections of water? To what cause, 
more than to all others, is the different height of tales owing? Explain this. Is it 
probable that the Moon exerts any influence of attraction on the atmosphere ? Why it 
rt probable .< Are the atmospheric tides sufficiently sensible to be appreciated ? 



THE SEASONS. 293 

CHAPTER XXIV. 

THE SEASONS — DIFFERENT LENGTHS OF THE DAYS AND NIGHTS. 

The vicissitudes of the seasons and the unequal lengths 
of the days and nights, are occasioned by the annual revo- 
lution of "the Earth around the Sun. with, its axis inclined to 
the plane of its orbit. 

The temperature of any part of the Earth's surface de- 
pends mainly, if not entirely, upon its exposure to the Sun's 
rays. Whenever the Sun is above the horizon of anyplace, 
that place is receiving- heat; when the Sun is below the 
horizon it is parting with it, by a process which is called 
radiation. The quantities of heat thus received and im- 
parted in the course of the year, must balance each other at 
every place, or the equilibrium of temperature would not be 
supported. 

Whenever, then, the Sun remains more than twelve hours 
above the horizon of any place, and less beneath, the gen- 
eral temperature of that place will be above the mean state; 
when the reverse takes place, the temperature, for the same 
reason, will be below the mean state. Now the continuance 
of the Sun above the horizon of any place, depends entirely 
upon his declination, or altitude at noon. About the 20th 
of March, when the Sun is in the vernal equinox, and con- 
sequently has no declination, he rises at six in the morning 
and sets at six in the evening ; the day and night are then 
equal, and as the Sun continues as long above our horizon 
as below it. his influence must be nearly the same at the 
same latitudes, in both hemispheres. 

From the 20th of March to the 21st of June, the days 
grow longer, and the nights shorter, in the northern hemi- 
sphere the temperature increases, and we pass from spring 
to mid-summer ; while the reverse of this takes place in the 
southern hemisphere. From the 21st of June to the 23d of 
September, the days and nights again approach to equality,, 
and the excess of temperature in the northern hemisphere 
above the mean state, grows less, as also its defect in the* 
southern; so that, when the Sun arrives at the autumnal 

How much greater is the attractite ■povx.r nf the Earth upon the Moon, then thti of 
the Moon upon the Earth) What occasions the vicissitudes of the seasons, and the 
unequal lengths of the days and nights ? Upon what does the temperature at diiierent 
places depend ? Under wl at circumstances do the tame places change their I 
ture ? Are the quantities of heat received and imparted, every year always equal it the 
Rime places ) Why is it so ) When 13 the temperature of a place above, and, v. hen is it 
mean state ! Upon what does the continuance of the Sun above the berieon of 
any place, depend ' When is the Sun as long above our horizon as below it ! Dunn ; 
what season of the year is the temperature increasing? What. at the same tin 
place in regard to the temperature, in the southern hemisphere? Durius whiit yo. 
tion of the year ls the temperature decreasing? 

25* 



294 THE SEASONS. 

equinox, the mean temperature is again restored. From 
the 23d of September until the 21st of December, our nights 
grow longer and the days shorter, ami the cold increases as 
before it diminished, while we pass from autumn to mid- 
winter, in the northern hemisphere, and the inhabitants of 
the southern hemisphere from spring to mid-summer. From 
'the 21st of December to the 20th of March, the cold relaxes 
as the days grow longer, and we pass from the dreariness 
of winter to the mildness of spring, when the seasons are 
completed, and the mean temperature is again restored. 
The same vicissitudes transpire, at the same time, in the 
southern hemisphere, but in a contrary order. Thus are 
produced the four seasons of the year. 

But I have stated not the only, nor. perhaps, the most 
efficient cause in producing the heat of summer and the cold 
of winter. If. to the inhabitants of the equator, the Sun 
were to remain 16 hours below their horizon, and only 8 
hours above it, for every day of the year, it is certain they 
would never experience the rigors of our winter; since it 
can be demonstrated, that as much heat falls upon the same 
area from a vertical Sun in 8 hours, as would fall from him, 
vU an angle of 60°, in 16 hours. 

Now as the Sun's rays fall most obliquely when the days 
are shortest, and most directly when the days are longest, 
these two causes, namely, the duration and intensity of 
the solar heat, together, produce the temperature of the dif- 
ferent seasons. The reason why we have not the hottest 
temperature when the days are longest, and the coldest 
temperature when the days are shortest, but in each case 
about a month afterwards, appears to be, that a body once 
heated, does not grow cold instantaneously, but gradually, 
and so of the contrary. Hence, as long as more heat comes 
from the Sun by day than is lost by night, the heat will irv- 
•orease, and vice versa. 

BEGINNING AND LENGTH OP THE SEASONS. 
h. m. s. 
Sun enters V$ (Winter begins) lS49,Dec. 21, 7 254(i BIT. Wash. 
" " ^ (Spring " ) 1850, March '20,8 5t i 38 •' »f 
" " O (Summer " ) " June 21st, 6 3 9 " «' 
11 u ^(Autumn " ) " Sent. 22J. 195821 «* '• 
• " " Y$(Winter " ) " Dec. 21, 132157 lt " 

rFar what reason ? Hurley what portion of Jhc year is the cofcl increasing J "Why is it so>* 
Whatchange of season*, then, takes place, i i the northern and southern hemispheres? 
VBM t jther changes complete the seasons of the year? Whence is it evident that the 
wnequtd lengths of the days and nights are not the only, nor perhaps the most efficient 
cai-.se at the heat of summer, and the culd of winter? What two causes produce the 
greatest vicissitudes of heat and mid ! Why, then, do we uot have the hottest 'veather 
«*h<ic .t&e days are longest, and the eoottwj I 



THE SEASONS. 295 

d. h. m. s. 

Sun in the Winter Signs . . . . 89 1 30 52 

'* •• Spring . . . . 9-2 21 6 31 

" " Summer . . . . 93 13 55 22 

" •' Autumn . . . 89 17 23 26 

" north of Equator (Spring and Summer) 156 11 1 53 

" south " (Winter and Autumn; 178 )8 54 18 

Longest north of the Equator, . . 7 16 7 35 

Length of the tropical year, beginning at ") 

the winter solstice 1849, and ending at > 365 5 56 11 

the winter solstice 1850, ) 

Mean or average length of the tropical year, 365 5 48 48 

The north pole of the Earth is denominated the elevated 
pole, because it is always about 23i° above a perpendicular 
to the plane of the equator, and the south pole is denomi- 
nated the depressed pole, because it is about the same dis- 
tance below such perpendicular. 

As the Sun cannot shine on more than one half the Earth's 
surface at a time, it is plain, that when the Earth is moving 
through that portion of its orbit which lies above the Sun. the 
elevated pole is in the dark. This requires six months, that 
is, until the Earth arrives at the equinox, when the elevated 
pole emerges into the light, and the depressed pole is turned 
away from the Sun for the same period. Consequently, 
there are six months day and six months night, alternately, 
at the poles. 

When the Sun appears to us to be in one part of the eclip- 
tic, the Earth, as seen from the Sun, appears in the point 
diametrically opposite. Thus, when the Sun appears in the 
vernal equinox at the first point of Aries, the Earth is actu- 
ally in the opposite equinox at Libra. The days and nights 
are then equal all over the world. 

As the Sun appears to move up from the vernal equinox 
to the summer solstice, the Earth actually moves from the 
autumnal equinox down to the winter solstice. The days 
now lengthen in the northern hemisphere, and shorten in the 
southern. The Sun is now over the north pole, where it is 
mid-day, and opposite the south pole, where it is midnight. 

As the Sun descends from the summer solstice towards 
the autumnal equinox, the Earth ascends from the winter 
solstice towards the vernal equinox. The summer days in 
the northern hemisphere having waxed shorter and shorter, 
now become again of equal length in both hemispheres. 

While the Sun appears to move from the autumnal equi- 
nox down to the winter solstice, the Earth passes up from 

Why is the north pole denominated the elevated pole ? Why is the south role de- 
nominated the depressed pole Why are there six months day and six months night, 
alternately at the poles? What is always the relative position of the Sun and Earth ia 
the ecliptic? Give an example. When do the days lengthen in the northern hemi- 
sphere, and shorten in the southern! When is it mid-day at the north pole, and mid- 
night at the south ! When do the summer days in the northern hemisphe:e grow 
6horter an.! shorter? 



296 THE SEASONS. 

the vernal equinox to the summer solstice ; the south pole 
comes into the light, the winter days continually shorten in 
the northern hemisphere, and the summer days as regularly 
increase in length in the southern hemisphere. 

While the Sun appears again to ascend from its winter 
solstice to the vernal equinox, the Earth descends from the 
summer solstice to the autumnal equinox. The summer 
days now shorten in the southern hemisphere, and the win- 
ter days lengthen in the northern hemisphere. 

When the Sun passes the vernal equinox, it rises to the 
arctic or elevated pole, and sets to the antarctic pole. When 
the Sun arrives at the summer solstice, it is noon at the 
north pole, and midnight at the south pole. When the Sun 
passes the autumnal equinox, it sets to the north pole, and 
rises to the south pole. When the Sun arrives at the win- 
ter solstice, it is midnight at the north pole and noon at the 
south pole ; and when the Sun comes again to the vernal 
equinox, it closes the day at the south pole, and lights up 
the morning at the north pole. 

There would, therefore, be 186? days during which the 
Sun would not set at the north pole, and an equal time 
during which he would not rise at the south pole; and 173$ 
days in which he would not set at the south pole, nor rise 
at the north pole. 

At the arctic circle, 23° 27£' from the pole, the longest 
day is 24 hours, and goes on increasing as you approach the 
pole. In latitude 67° IS' it is 30 days ; in lat. 69° 30' it is 
60 days, &c. The same takes place between the antarctic 
circle and the south pole, with the exception, that the day in 
the same latitude south is a little shorter, since the Sun is 
not so long south of the equator, as at the north of it. In 
this estimate no account is taken of the refractign of the 
atmosphere, which, as we shall see hereafter, increases the 
length of the day, by making the Sun appear more elevated 
above the horizon than it really is. 

When do they become of equal length in both hemispheres? When do the winter dajt 
shorten in the northern hemisphere, and the summer days lengthen in the southern? 
When do the summer days shorten in the southern hemisphere, and the winUrdnys 
lengthen in the northern? When does the. Sun rise to the north pole, and set to the 
south' When is it noon at the north pole, and midnight at the south i ole ? When 
does the Sun set to the north pole, and rise to the south > When is it midnight at the 
north pole, and noon at the south? What, is the length of the day at the i-o th pole? 
What at the south pole? At the arctic circle? Between the antarctic circle at:d the 
pole? 



THE SEASONS. 



297 



THE SEASONS — UNEQUAL LENGTHS OF DAYS AND NIGHTS 




Ternal Equino^ 




The above cut represents the inclination of the earth's axis to its orbit in every 
one of the twelve signs of the ecliptic, and consequently for each montli in the 
year. It is such a view as a beholder would have, situated in the north pole of 
the ecliptic, at some distance from it, and consequently, is a perpendicular 
view, the north pole of the Earth being towards us. The Sun enters the sign 
Aries, or the vernal equinox, on the 20th of March, when the Earth's axis in- 
clines neither towards the Sun, nor Jrom it, but stands exactly sideways to it ; 
so that the Sun then shines equally upon the Earth from pole to pole, and the 
days and nights are every where equal. This is the beginning of the astronomi- 
cal year ; it is also the beginning of day at the north pole, which is just coming 
into light, and the end of day at the south pole, which is just, going into darkness. 

By the Earth's orbitual progress, the Sun appears to enter the secoud sign, 
Taurus, on the 20th of April, when the north pole has sensibly advanced into 
the light, while the south pole has been declining from it ; whereby the days 
become longer than the nights in the northern hemisphere, and shorter in the 
southern. 

On the 21st of May, the Sun appears to enter the sign Gemini, when the 
north pole has advanced considerably further into the light, while the south 

f)ole has proportionally declined from it ; the summer days are now waxing 
onger in the northern hemisphere, and the nights shorter. 

The 21st of June, when the Sun enters the sign Cancer, is the first day of 
summer in the astronomical year, and the longest day in the northern hemi- 
sphere. The north pole now has its greatest inclination to the Sun, the light of 
which, as is shown by the boundary of light and darkness, in the figure, ex- 
tends to the utmost verge of the Arctic Circle : the whole of which is included 
in the enlightened hemisphere of the Earth, and enjoys, at this season, constant 
day during the complete revolution of the Earth on its axis. The whole of the 
Northern Frigid Zone is now in the circle of perpetual illumination. 
On the 23d of July, the Sun enters the sign Leo, amJ as the line of the 



298 UNEQUAL LENGTHS OF DAYS AND NIGHTS. 

Earth's axis always continues parallel to itself, the boundary of light and dark- 
ness begins to approach nearer to the poles, and the length of the day in the 
northern hemisphere, which hail arrived at its maximum, begins gradually to 
decrease. On the 23d of August, the Sun enters the sign Virgo, increasing 
the appearances mentioned in Leo. 

On the 23d of September, the Sun enters Libra, the first of the autumnal 
signs, when the Earth's axis having the same inclination as it had in the oppo- 
site sign, Aries, is turned neither from the Sun, nor towards it. but obliquely 
to it, so that the Sun again now shines equally upon the whole of the Earth's 
surface from pole to pole. The days and nights are once more of equal length, 
throughout the world. 

On the 23d of October, the Sun enters the sign Scorpio; the days visibly 
decrease in length in the northern hemisphere, and increase in the southern'. 

On the 22d of November, the Sun enters the sign Sagittarius, the last of 
the autumnal signs, at which time the boundary of light and darkness is at a 
considerable distance from the north pole, while the south pole has proportion- 
ally advanced into the light; the length of the day continues to increase in the 
southern hemisphere, and to decrease in the northern. 

On the 21st of December, which is the period of the winter solstice, the Sun 
enters the si<:n Capricorn. At this time, the north pole of the Earth's axu is 
turned from the Sun. into perpetual darkness: while the south pole, in its turn, 
is brought into the light of the Sun. whereby the whole Antarctic region comes 
into the circle of perpetual illumination. It is now that the southern hemi- 
sphere enjoys all those advantages with which the northern hemisphere was fa- 
vored on the 2lst of June ; while the northern hemisphere, in its turn, under- 
goes the dreariness of winter, with short days and long nights. By carefully 
observing the figure, it will be seen that the orbit of the Earth is slightly ellip- 
tical, that the Sun is to the right of the center, and that consequently, the Earth 
is nearer the Sun on the 21st of December, than on the opposite side of the 
ecliptic, on the 21st of June. This may seem strange to the learner, that 
we should have our winter when nearest the Sun, and our summer when most 
distant; but it must be remembered, that ttte temperature of any particular 
part of the Earth is not so much affected by the distance of the Sun, as by the 
directness or obliquity of his rays. Hence, though we are farther from the Sun 
on the 21st of June than on the 21st of December, yet, as the north poie of the 
Earth is turned more directly into the light, at that time, so that the suit's rays 
strike her surface less obliquely than in .December, we have a higher tempera- 
ture at that period, though at a greater distance from the Sun. 

The difference, however, between the aphelion and perihelion distances of 
the Earth, is so slight, in comparison with the whole distance, as scarcely to 
cause a perceptible difference in the amount of light received at her respective 
positions. The eccentricity of the Earth's orbit, or the distance of the S"tn from 
its center, is only about 1*613,000 miles, so that the variation is only 3,236,000 
miles, or about one-thirtieth of the mean distance. In the preceding cut 
the eccentricity is exaggerated to one-eighth the mean distance, making the 
difference between the Earth's perihelion and aphelion distance to amount to 
one quarter, or 23.777.777 miles. This is more than seven times its real 
amount, and yet the ellipticity is scarcely perceptible. The true orbit of the 
Earth could not be distinguished from a circle. 

The only effect of the eccentricity of the earth's orbit 
upon her temperature is, that she has probably a greater 
degree of heat, during summer in the southern hemisphere, 
when the Earth is at her perihelion, than we ever have at 
the north in the same latitude. But this dilference must be 
very slight, if indeed it is at all perceptible. 



HARVEST MOON. 299 



CHAPTER XXY. 

HARVEST MOON HORIZONTAL MOON. 

The daily progress of the Moon in her orbit, from west 
to east, causes her to rise, at a mean rate, 48 minutes and 
44 seconds later every day than on the preceding. But 
in places of considerable latitude, a remarkable deviation 
from this rule takes place, especially about the lime of 
harvest, when the full Moon rises to us for several nights 
together, only from 18 to 25 minutes later in one day, than 
on that immediately preceding. From the benefit which 
her light affords, in lengthening out the day, when the hus- 
bandmen are gathering in the fruits of the Earth, the full 
moon, under these circumstances, has acquired the name of 
Harvest Moon. 

It is believed that this fact was observed by persons engaged in agriculture, 
at a much earlier period than that in which." it was noticed by astronomers. 
The former ascribed it to the goodness of the Deity; not doubting but that he 
had so ordered it for their advantage. 

About the equator, the Moon rises throughout the year 
with nearly the equal intervals of 48? minutes; and there 
the harvest Moon is unknown. 

At the polar circles, the autumnal full Moon, from her first 
to her third quarter, rises as the Sun sets ; and at the poles, 
where the Sun is absent during one half of the year, the 
winter full Moons, from the first to the third quarter, shine 
constantly without setting. 

Bv this, it. is not meant that the Moon continues full from her first to her 
third quarter : but that she never set* to the North Polar regions, when, at this 
season of the year, she is within 90° of that point in her orbit where she is at 
her full. In other words : as the Sun illumines the south pole during one half 
of its yearly revolution, so the Moon, being opposite to the Sun at her full, 
must illumine the opposite pole, during half of her revolution about the Earth. 
The phenomenon of the harvest Mooii may be thus exemplified by means of 
the globe : 

Rectify the slobe to the latitude of the place, put a patch or piece of wafer in 
the ecliptic, on the point Aries, and mark every 12" preceding and following 
that point, to the number of ten or twelve mark's on each side of it ; bring the 
equinoctial point marked by the wafer to the eastern edge of the horizon, and 
set the index to 12 ; turn the globe westward till the other marks successively 
come to the horizon, and observe the hours passed over by the index; the in- 
terval of time between the marks coming to the horizon, will show the diurnal 
difference of time between the Moon's i-ising. If these marks be brought to 
the western edse of the horizon in the sanie manner, it will show the diur- 
nal difference between the Moon's setting. 

From this problem it will also appear, that, when there is the least difference 
between the times of the Moon's rising, there will be the greatest difference 
between the times of her setting-, and the contrary. 

What is the mean difference of time in the daily rising of the Moon? Under what cir- 
ces is there a material deviation from this rule ! Whence the name i ! 
< phenomenon ftrst rMerved. and to irhat ■ 
it ? Why is the harvest 3Ioon unknown at the equator? How is it at the pola 
and the poles' II shining from the first to the third 

quarter I Horn may the phenomenon be exemplified by means of the artificial globe? 
Why do you mark every 12° of the ecliptic in this problem! 



300 HARVEST MOON. 

The reason why you mark every 12° is, that the Moon pains 12° 11' on th« 
apparent course of the Sun every day, and these marks serve to denote the 
place of the Moon from day to day. 'it is true, this process supposes that the 
Moon revolves in the plane of the ecliptic, which is not the case ; yet her orbit 
so nearly coincides with the ecliptic, (differing only 5° 9' from it,) that they 
may, for the convenience of illustration, be considered as coinciding; that is, 
we may take the ecliptic for the representative of the Moon's orbit. 

The different lengths of the lunar night, at different lati- 
tudes, is owing to the different angles made by the horizon 
and different parts of the Moon's orbit; or in other words, 
by the Moon's orbit lying sometimes more oblique to the 
horizon than at others. In the latitude of London, for ex- 
ample, as much of the ecliptic rises about Pisces and Aries 
in two hours as the Moon goes through in six days ; there- 
fore while the Moon is in these signs, she differs but two 
hours in rising for six days together; that is, one day with 
another, she rises about 20 minutes later every day than on 
the preceding. 

The parts or signs of the ecliptic which rise with the 
smallest angles, set with the greatest ; and those which rise 
with the greatest, set with the least. And whenever this 
angle is least, a greater portiofi of the ecliptic rises in equal 
times than when the angle is larger. Therefore, when the 
Moon is in those signs which rise or set with the smallest 
angles, she rises or sets with the least difference of time ; 
but when she is in those signs which rise or set with the 
greatest angles, she rises or sets with the greatest difference 
of time. 

Let the globe, for example, be rectified to the latitude of New York, 4CP 4ii* 
40", with Cancer on the meridian, and Libra rising in the east. In this posi- 
tion, the ecliptic has a high elevation, making an angle with the horizon of 72£°. 

But let the globe be turned half round on its axis, till Capricorn comes to 
the meridian, and Aries rises in the east, then the ecliptic will h;ive a low ele- 
vation above the horizon, making an angle with it of only 25,±*. This angle is 
47° less than the former angle, and is equal to the distance' between the tropics. 

In northern latitudes, the smallest angle made by the 
ecliptic and horizon is when Aries rises; at which time Li- 
bra sets; the greatest is, when Libra rises and Aries sets. 
The ecliptic rises fastest about Aries, and slowest about 
Libra. Though Pisces and Aries make an angle of only 
25j° with the horizon ichen they jise, to those who live in 
the latitude of New York, yet the same signs, when they set, 
make an angle of 72£°. The daily difference of the Moon's 
rising, when in these signs, is, in New England, about 22 

Whttt does this process of illustration suppose, which is not true, and wliij is it 
adopted! To what is tbe different length* of the lunar night, in ditleret.t latitudes, ow- 
ing i Give an example. How do those parts ul the ecliptic set, which rise with tba 
smallest angles, and the contrary t 

What lesults from this in regard to Die Moon' How may this be illustrated on tM 
globe' In ik) thern latitudes, what 9igns rise and set wiih ttie least angles :< What with 
the greatest Which puns i. •«i> ' ri-r- i,s,,„t. ;md which slowest? Give an ex- 
ample. What is the dm!y diligence oi" the M< oil's rising and setting, in these sigus, in 
the latitude of New York' 



HARVEST MOON. 301 

minutes ; but when she is in the opposite signs, Virgo and 
Libra, the daily difference of her rising is almost four times 
as great, being about, one hour and a quarter. 

As the Moon can never be full but when she is opposite 
to the Sun, and the Sun is never in Virgo or Libra except, in 
our autumnal months, September and October, it is evident 
that the Moon i3 never full in the opposite signs. Pisces and 
Aries, except in those two months. We can therefore have 
only two full Moons in a year, which rise, for a week togeth- 
er, very near the time of Sun-set. — The former of these is 
called the Harvest Moon, and the latter, the Hunters Moon. 

Although there can be but two full Moons in the year that 
rise with so little variation of time, yet the phenomenon of 
the Moon's rising for a week together so nearly at the same 
time, occurs every month, in some part of her course or the 
other. 

In Winter, the signs Piscos and Aries rise about noon ; hence the rising of 
the Moon is not then regarded nor perceived. 

In Spring, these signs rise with the Sun, because he is then in them ; and as 
the Moon changes while passing through the same sign with the Sun. it must 
then be the change, and hence invisible. 

In Summer, they rise about midnight, when the M >on is in her third quar- 
ter. On account of her rising so late, and giving hut little light, her rising 
passes unobserved. 

To the inhabitants at the equator, the north and south 
poles appear in the horizon; and therefore the ecliptic makes 
the same angle southward with the horizon when Aries rises, 
as it does northward when Libra rises ; consequently the 
Moon rises and sets not only with angles nearly equal, but 
at equal intervals of time, all the year round ; hence, there 
is no harvest Moon at the equator. The farther any place 
is from the equator, if it be not beyond the polar circles, the 
angle which the ecliptic makes with the horizon gradually 
diminishes when Pisces and Aries rise. 

Although in northern latitudes, the autumnal full Moons 
are in Pisces and Aries; yet in southern latitudes it is just 
the reverse, because the seasons are so: — for Virgo and Li- 
bra rise at as small angles with the horizon in southern .lati- 
tudes, as Pisces and Aries do in the'nonhern ; and therefore 
the harvest Moons are just as regular on one side of the 
equator as on the other. 

At the polar circles, the full Moon neither rises in summer, 
nor sets in winter. For the winter full Moon being as high 
in the ecliptic as the summer Sun, she must continue, while 

How many full Moons in a year, which rise with so little difference of time 7 Why 
are not these phenomena observed hi the samt signs, in winter, spring, and summer > 
Explain why there is no Harvest Moon at the equator. The fan her any place is from 
the equator, how is the angle between the ecliptic and the horizon, when Pities and 
Aries rise? Do the Harvest Moons happen as regularly, and in the same months, ou 
the south side of the equator, as on the north"! Why does not the full Moon rise in 
summer/or set in winter, to the inhabitants of the polar circles ? 

26 



302 REFRACTION. 

passing through the northern signs, above the horizon; and 
the summer full Moon being as low in the ecliptic as the win- 
ter Sun, can no more rise, when passing through the south- 
ern signs, than he does. 

THE HORIZONTAL MOON. 

The great apparent magnitude of the Moon, and indeed 
of the Sun, at rising and setting, is a phenomenon which hag 
greatly embarrassed almost all who have endeavored to ac- 
count for it. According to the ordinary laws of vision, they 
should appear to be least when nearest the horizon, being 
then farthest from the eye ; and yet the reverse of this is 
found to be true. The apparent diameter of the Moon, when 
viewed in the horizon by the naked eye, is two or three times 
larger than when at the -altitude of thirty or forty degrees; 
and yet when measured by an instrument, her diameter is 
not increased at all. 

Both the Sun and the Moon subtend a greater angle when on the meridian, 
than they do in the horizon, because they are then actually nearer the place of 
the spectator, by the whole semi-diameter of the Earth. 

This apparent increase of magnitude in the horizontal 
Moon, is chiefly an optical illusion, produced by the concav- 
ity of the heavens appearing to the eye to be a less portion 
of a spherical surface than a hemisphere. The eye is ac- 
customed to estimate the distance between any two objects 
in the heavens by the quantity of sky that appears to lie be- 
tween them ; as upon the Earth we estimate it by the quan- 
tity of ground that lies between them. Now when the Sun 
or Moon is just emerging above the eastern horizon, or sink- 
ing beneath the western, the distance of the intervening 
landscape over which ihey are seen, contributes, together 
with the rpfraction of the atmosphere to exaggerate our 
estimate of their real magnitudes. 



CHAPTER XXVI. 

REFRACTION— TWILIGHT. 

The rays of light in passing out of one medium into ano- 
ther of a greater density, deviate from a straight course, 
and are bent towards a perpendicular to that course ; and 

According to the ordinary laws of vision, how 0112 ht the magnitudes of the Sun and 
Moon to appear when they ;.re nearest the horizon.' What is Ihefuct? Ilowmueh 
larger does the .Moon appear to the naked eye. when in the horizon, than when at the 
altitude of thirty or forty degrees .' When, in reality, do th' 1 mbtend 

the largfM angle 1 Why is it so ; How is the apparent increase of magnitude in th* 
horizontal Moon accounted for. 



REFRACTION. 



303 



if the density of the latter medium continually increase, the 
raysof light in passing through it, will deviate more and 
more from a right line as they pass downwards, or towards 
the eye of the observer. This principle is illustrated by the 
following cut. 



REFRACTION OF LIGHT. 




The light emanating from the luminous body of A strikes 
the water at B. and is bent out of its course towards the per- 
pendicular D D. The rays B C are the refracted rays, and 
the angle they make at B the angle of refraction. 

It will be seen further by the diagram that the amount 
of the angle of refraction is in proportion to the obliquity of 
the rays. At B they are more refracted than at E. and at 
F, where the light strikes the water perpendicularly, it is 
not refracted at all. 

The principles here illustrated hold good in regard to all 
transparent substances, whether fluids or solids, and all kinds 
of surfaces. Glass will refract light as well as water, and a 
convex surface as well as a plain one; and in all cases the 
angle of incidence (or contact with the denser substance) 
and the angle of refraction are proportionate. Hence a 
lens made of glass, having two convex surfaces, will refract 
all the light that falls upon it, to a point called its locus, in the 
center, which point will be near or remote, according to the 

How are the rnys of light affected in passing out of one medium into another, of a 
different density? How, if the den.sily oi' the latter medium continually increase ' 



304 



REFRACTION. 



convexity or flatness of the lens. The annexed cut furnishes 
the necessary illustration. 

LIGHT REFRACTED BY GLASS LENSES. 



By sending a beam of light through a triangular piece of 
glass, called a. prism, it is found that all parts of the beam 
are not refracted alike, or in other words that light is a 
compound substance, some of whose elements are more 
refrangible than others. The red light is refracted least, 
the orange nexi, and so on to violet, the most refrangible of 
all the primary colors. 





In the cut the light from A instead of passing in straight 
lines to B, is refracted by the prism C towards the point D ; 
and thus, by the difference of their refrangibility, the com- 
ponent parts of the white beam are separated. 

In a similar manner the light is analyzed by refraction in 
the formation of the rainbow, and also "in the production of 



What astronomical pnerv 



the rays of light out of their course called 



lis from this cause ? What is this bending c/ 



REFRACTION. 



305 



the various tints that often adorn the morning and evening 
sky. 

ATMOSPHERICAL REFRACTION. 

In passing from its source to the surface of the earth, the 
light of the heavenly bodies is refracted by the atmosphere, 
as in passing from the atmosphere into glass or water. It 
is on this account that all celestial bodies, except when in 
the zenith appear higher than they really are. as illustrated 
m tb^a following figure. 



ATMOSPHERICAL REFRACTION. 




Here the light emanating from the Sun at A, strikes the 
atmosphere obliquely at B. and is refracted downwards to the 
beholder at C ; so that the Sun is actually seen in the horizon, 
or in the direction of the last line of light, before he has 
reached that elevation. A little farther up, the light is seen to 
strike the atmosphere less obliquely, is refracted less, and 
leaves less difference between the true and the apparent 
place. Still nearer the zenith the refraction is still less, till 
finally, the rays falling perpendicularly are not refracted at 
all. From the zenith westward, the refraction and conse- 
quent difference between the Sun's true and apparent place 
increases, till at E the Sun is seen after he is below the ho- 
rizon. 

At some periods of the year the Sun appears 5 minutes 
longer, morning and evening, and about 3? minutes longer 

What effect does refraction hu*e upon the apparent rising and setting of the heavenly 
bodies 1 How much longer do we see the Sun, morning and evening, than we should 
if there were no refraction ? 

26* 



306 REFRACTION. 

every dzy, at a mean rate, than he would do were there no 
refraction. The average amount of refraction for an object 
haif way between the horizon and the zenith, or at an ap- 
parent altitude of 45°, is but one sixtieth of a degree, a 
quantity hardly sensible to the naked eye ; but at the visible 
horizon it amounts to 33' of a degree, which is rather more 
than the greatest apparent diameter of either the Sun or 
the Moon. 

Hence it follows, that when we see the lower edge of the 
Sun or Moon just apparently resting on the horizon, their 
whole disc is in reality below it, and would be entirely out 
of sight and concealed by the convexity of the Earth, but for 
the bending, which the rays of light have undergone in their 
passage through the air to the observer's eye. 

The following general notions of its amount, and law of 
variations, should be borne in mind: 

1. In the zenith there is no refraction ; a celestial object, 
situated directly overhead, is seen in its true position, as if 
there were no atmosphere. 

2. In descending from the zenith to the horizon, the 
refraction continually increases ; objects near the horizon 
appearing more elevated by it than those of a higher 
altitude. 

3. The rate of its increase is nearly in proportion to the 
apparent angular distance of the object from the zenith. 
But this rule, which is not far from the truth, at moderate 
zenith distances, ceases to give correct results in the vicinity 
of the horizon, where the law becomes much more compli- 
cated in its expression. 

The effects of refraction must he familiar to every person who has seen a 
walking-stick partially plunged into a river, or other collection of water. 
While the stick is held upright, it appears straight, as usual, because there is 
no refraction in this position : hut if it be ever so little inclined, the refraction 
takes place, and the stick appears bent ; if the inclination be increased, the 
refraction is also increased. 

Another easy and familiar illustration of the effect of refraction may he thus 
obtained : — Put any small object, as a piece of money, into an empty "basin, as 
near the center aspossible, and retire to such a distance as just to lose Bight of 
the object. Let an assistant then pour water in the basin, and the object will 
soon reappear. Retire agnin till it is no longer seen ; let more water be added, 
and it will again appear. The experiment may be repeated till the basin is lull 
The edge of the basin may be supposed to represent the horizon ; the water, 
the atmosphere; and the piece of money, the Sun, or other object which is 
thus made to appear by the power of refraction, when otherwise it would 
be invisible. 

In this illustration, the light from the object at A. is intercepted by the side of 
the empty vessel at B, so that it remains invisible to the beholder on the right ; 
but when the vessel is filled with water, the light from the object on reach- 

What is the average amount of refraction for an object halfway between the horizon 
and the zenith' What is it in the horizon? What interesting facts result from this 
truth? What is the first general law of atmospheric refraction ? What is the second 
general law ? What is the third? Menliun a familiar instance of refractx 
Been in water. Menfujn *mne familiar experiment, to illustrate refraction, and ilwio 
its application to astronomy. 





REFRACTION. 307 

CURIOUS RESULT OP REFRACTION. 



.tf-O' 



frig the surface at C. is retracted in a horizontal direction ; and by its thus reach- 
ing the eye of the observer the object is rendered visible, though the side of the 
vessel actually intervenes between it and him. 

From what has been said of the amount of refraction 
when the luminous body is in or near the horizon, it must 
be obvious that one of its effects must be to shorten the 
duration of night and darkness, by prolonging the apparent 
stay of the Sun and Moon above the horizon. But even 
after they appear to have set. the influence of the atmosphere 
still continues to send us a portion of their light; not, indeed, 
by direct transmission, but by reflection : — for as long as the 
Sun continues to illuminate any portion of the atmosphere 
which is above the horizon, the light from this portion is 
reflected to the Earth, and it is this that causes twilight. 

In the morning, when the Sun arrives at 18° below the 
horizon, his rays pass over our heads into the higher region 
of the atmosphere, and are thence reflected, or as it were. 
bent down to the Earth. The day is then said to dawn, and 
the light gradually increases until the Sun appears above 
the horizon : this is called Morning Tirilight, or Aurora, 
which the heathens personified as a goddess. They assigned 
to her the office of opening the Gates of the East, to intro- 
duce the chariot of Apollo or Phcebus. 

In the evening, after sunset, the rays of the Sun continue 
to illuminate the atmosphere, till he sinks IS below the 
horizon, and a similar effect, called the Evening Twilight. 
is produced, only in an inverse progression, for the twilight 
now gradually becomes fainter till it is lost in dark night. 

The quantity of reflection and the duration of twilight 

How docs this principle affect the duration of nocturnal darkness? By what prin- 
ciple is it that the atmosphere sends us a portion of the solar light, for a considerable 
time before the Sun rises, and after it has Bet? What is Twilight! How is it occa- 
sioned? How is the evening twilight, produced? By what are the quantity of reflec- 
tion, and the duration of twilight, considerably influenced ? Why is twilight shorter in 
winter ? 



308 REFRACTION, 

are much influenced by the changes which are perpetually 
taking place with respect to the heat and cold, the drynew 
or moisture, &c, of the atmosphere. The height of the at- 
mosphere, also, has an influence in determining the duration 
of twilight. Thus in winter, when the air is condensed with 
cold, and the atmosphere upon that account lower, the iwi- 
light will be shorter ; and in summer, when the limits of the 
jatmosphere are extended by the rarefaction and dilation of 
the air of which it consists, the duration of the twilight will 
be longer. And for the same reason, the morning twilight, 
(the air being at that time condensed and contracted by the 
cold of the preceding night ) will be shorter than the even- 
ing twilight, when the air is more dilated and expanded. 

It is entirely owing to the reflecting 'power of the atmos- 
phere that the heavens appear bright in the dny-time. For 
without such a power, only that part of the heavens would 
be luminous in which the Sun is placed ; and, if we should 
turn our backs to the Sun, the whole heavens would appear 
as dark as in the night, and the stars, even at noon-day, 
would be seen as clear as in the nocturnal sky. 

In regions of the Earth situated towards the poles, the 
Sun, during their summer months, is never more than 1S° 
below the horizon; consequently their twilight continues 
during the whole night. The same cause has a tendency 
to diminish the gloom of the long polar nights ; for as far 
north as in lat. S4° 32£' the Sun, even when at the winter 
solstice, approaches to within 18° of the horizon, and affords 
a short twilight once in 24 hours, and the pole itself is left 
in total darkness not more than 80 days. 

There is still another cause which has a tendency to 
diminish the length of the polar nights, the extraordinary 
refraction occasioned by the extreme density of the air in 
those regions. This is so great, as to bring the Sun above 
the horizon some days before it should appear, according to 
calculation. 

A remarkable phenomenon of this kind was observed by the Dutch navigators 
who wintered in Nova Zembla, in the year 1596. After en< luring a continual 
night of three months, they were agreeably surprised to find that the Sun began 
to rise seventeen days sooner than according to computation ! The observed 
altitude of the pole at the place, (says Dr. Smith,) being only 76°. it is impossi- 
ble to account for the phenomenon, otherwise, than by supposing an extraor- 
dinary refraction of the Sun's rays. Kepler computes that the Sun was almost 
5° below the horizon when he first appeared; and consequently, that the re- 
fraction of his rays was about 10 times greater than with us. 

Why longer in summer? Why is the morning twilight shorter than the evening 
twilight? To what is it entirely owine.that the heavens appear bright in the day-time » 
How would the heavens appear, if it were not for this power? What are the dura- 
tion and advantages of twilight in high latitudes ? Rela:e a remarked) e pheno?ttenon 
cf this kind. How are the phenomena of the Aurora Borealis regarded by the igno- 
rant? In what, do all acree, respecting them? Where are these appearances most fre- 
quent and brilliant? Describe the times and manner of their appearance 



AURORA EOREALIS. 309 

CHAPTER XXYII. 

AURORA BOREALIS. 

The sublime and beautiful phenomena presented by the 
Aurora Borealis, or northern lights, as they are called, 
have been in all ages a source of admiration and wonder 
alike to the peasant and the philosopher. In the regions of 
the north, they are regarded by the ignorant with supersti- 
tious dread, as harbingers of evil ; while all agree in placing 
them among the unexplained wonders of nature. 

These lights, or meteoric coruscations, are more brilliant 
m the arctic regions, appearing mostly in the winter season 
and in frosty weather. They commonly appear at twilight 
near the horizon, and sometimes continue in that state for 
several hours without any sensible motion; after which they 
send forth streams of stronger light, shooting with great 
velocity up to the zenith, emulating, not unfrequently. the 
lightning in vividness, and the rainbow in coloring ; and 
again, silently rising in a compact majestic arch of steady 
white light apparently durable and immovable, and yet 
so evanescent, that while the beholder looks upon it, it is 
gone. 

At other times, they cover the whole hemisphere with 
their flickering and fantastic coruscations. On these occa- 
sions their motions are amazingly quick, and they astonish 
the spectator with rapid changes of form. They break out 
in places where none were seen before, skimming briskly 
along the heavens ; then they are suddenly extinguished, 
leaving behind a uniform dusky track, which, again, is bril- 
liantly illuminated in the same manner, and as suddenly left 
a dull blank. Some nights they assume the appearance of 
vast columns; exhibiting on one side tints of the deepest 
yellow, and on the other, melting away until they become 
undistinguishable from the surrounding sky. They have 
generally a strong tremulous motion from end to end." which 
continues till the whole vanishes. 

Maupertius relates, that in Lapland. " the sky was some- 
times tinged with so deep a red that the constellation Orion 
looked as though it were dipped in blood, and that the peo- 
ple fancied they saw armies engaged, fiery chariots, and a 
thousand prodigies." Gmelin relates, that, "in Siberia, on 
the confines of the icy sea. the spectral forms appear like 
rushing armies ; and that the hissing, crackling noises of 

i Lapland a3 related by Maupertius, and its effect upon the 



310 AURORA BOREALIS. 

those aerial fire-works so terrify the dogs and the hunters, 
that they fall prostrate on the ground, and will not move 
while the raging host is passing." 

Kerguelen describes " the night, between Iceland and the 
Fcrro Islands, as brilliant as the day" — the heavens being 
on fire with flames of red and white light, changing to col- 
umns and arches, and at length confounded in a brilliant 
chaos of cones, pyramids, radii, sheaves, arrows, and globes 
of fire. 

But the evidence of Capt. Parry is of more value than 
that of the earlier travelers, as he examined the pheno- 
mena under the most favorable circumstances, during a 
period of twenty-seven consecutive months, and because his 
observations are uninfluenced by imagination. He speaks 
of the shifting figures, the spires and pyramids, the majestic 
arches, and the sparkling bands and stars which appeared 
within the arctic circle, as surpassing his powers of descrip- 
tion. They are indeed sufficient to enlist the superstitious 
feelings of any people not fortified by religion and phi- 
losophy. 

The colors of the polar lights are of various tints. The 
rays or beams are steel gray, yellowish gray, pea green, 
celandine green, gold yellow, violet blue, purple, sometimes 
rose red. crimson red, blood red, greenish red, orange red, 
and lake red. The arches are sometimes nearly black, 

Eassing into violet blue, gray, gold yellow, or white bounded 
y an edge of yellow. The lustre of these lights varies in 
kind as well as intensity. Sometimes it is pearly, some- 
times imperfectly vitreous, sometimes metallic. Its degree 
of intensity varies from a very faint radiance to a light 
nearly equaling that of the Moon. 

Many theories have been proposed to account for this 
wonderful phenomenon, but there seems to be none which 
is entirely satisfactory. One of the first conjectures on record 
attributes it to inflammable vapors ascending from the Earth 
into the polar atmosphere, and there ignited by electricity. 
Dr. Halley objects to this hypothesis, that the cause was 
inadequate to produce the effect. He was of opinion that 
the poles of the Earth were in some way connected with the 
aurora ; that the Earth was hollow, having within it a mag- 
netic sphere, and that the magnetic effluvia, in passing from 
che north to the south, might become visible in the northern 
hemisphere. 

Describe its appearance between Iceland and the Ferro Islands, as related by Kerjue- 
len. Whose testimony on this subject is of more value than that of former travelers? 
Why? How does he describe the scenes he witnessed durin? the polar nighu? 
Describe the colors of the Aurora light. What is one of the earliest theories advanced 
to explain this phenomenon? How did Dr. Halley propose to account tor it' What 
observations have led pretty generally to the conclusion, that the northern lights are to 
some extent a magnetical phenomenon? 



AURORA BOREALIS. 311 

That the aurora borealis is, to some extent a magnetical 
phenomenon, is thought, even by others, to be pretty clearly 
established by the following considerations. 

1. It has been observed, that when the aurora appears 
near the northern horizon in the form of an arch, the middle 
of it is not in the direction of the true north, but in that of 

" e magnetic needle at the place of observation; and that 
»* the arch rises towards the zenith, it constantly crosses 
.ue heavens at right angles, not to the true magnetic meri- 
dian. 

2. When the beams of the aurora shoot up so as to pas3 
the zenith, which is sometimes the case, the point of their 
convergence is in the direction of the prolongation of the 
dipping needle at the place of observation. 

3. It has also been observed, that during the appearance 
of an active and brilliant aurora, the magnetic needle often 
becomes restless, varies sometimes several degrees, and does 
not. resume its former position until after several hours. 

From these facts, it has been generally inferred that the 
aurora is in some way connected with the magnetism of 
the Earth ; and that the simultaneous appearance of the 
meteor, and the disturbance of the needle, are either related 
as cause and effect, or as the common result of some more 
general and unknown cause. Dr. Young, in his lectures, 
is very certain that the phenomenon in question is intimately 
connected with electro-magnetism, and ascribes the light of 
the aurora to the illuminated agency of electricity upon the 
magnetical substance. 

It may be remarket 1, in support of the electro-magnetic theory, that in mag- 
netism. "the agency of electricity is now clearly established ; and it can hardly 
be doubted that the phenomena both of electricity and magnetism are produced 
by one and the same cause ; inasmuch as magnetism may be induced by elec- 
trichy. and the electric spark has been drawn from the magnet. 

Sir John Herschel also attributes the appearance of the 
aurora to the agency of electricity. This wonderful agent, 
says he. which we see in intense activity in lightning, and 
in a feebler and more diffused form traversing the upper 
regions of the atmosphere in the northern lights, is present, 
probably, in immense abundance in every form of matter 
which surrounds us, but becomes sensible, only when dis- 
turbed by excitements of peculiar kinds. 

What is the opinion orDr. Young in regard to their cause ? What consideration may 
be adduced in fanner support of the elfdtro-magnetie theory! To what does Sir John 
Herschel MSt-rioe the aurora.' What are his observations upon the subject > What is par- 
allax .» What isthe true place of a celestial body? "What is the apparent place? Where 
is the parallax of a heavenly body the greatest? What is this paridiux cahtd 1 



312 



PARALLAX OF THE HEAVENLY BODIES. 



CHAPTER XXVIII. 



PARALLAX OF THE HEAVENLY BODIES. 

Parallax is the difference between the altitude of any- 
celestial object, seen from the Earth's surface, and the alti- 
tude of the same object seen at the same lime from the 
Earth's center; or ; it is the angle under which the semi- 
diameter of the Earth would appear, as seen from the 
object. 

The true place of a celestial body, is that point of the 
heavens in which it would be seen by an eye placed at the 
center of the Earth. The apparent place i.s that point of 
the heavens where the body is seen from the surface of 
the Earth. The parallax of a heavenly body is greatest, 
when in the horizon ; and is called the horizontal parallax. 
Parallax decreases, as the body ascends toward the zenith, 
at which place it is nothing. 

The following cut will afford a sufficient illustration. 




Apparent *~~pTacc 



PARALLAX. 



When the observer, standing upon the Earth at A, views 
the object at B, it appears to be at C, when, at the same 
time, if viewed from the center of the Earth it would appear 



PARALLAX OF THE HEAVENLY BODIES. 313 

to be at D. The parallax is the angle B C D or B A I, 
which is the difference between the altitude of the object B, 
when seen from the Earth's surface, and when seen from 
her center. It is also the angle under which the semi- 
diameter of the Earth. A I, is seen from the object B. 

As the object advances from the horizon to the zenith, the 
parallax is seen constantly to diminish, till at H. it has no 
parallax, or its apparent and true, place are the same. 

This diagram will also show why objects nearest the 
Earth have the greatest parallax, and those most distant 
the least — why the Moon, the nearest of all the heavenly 
bodies, has the greatest parallax, while the fixed stars, from 
their immense distance, have scarce any appreciable paral- 
lax, the semi-diameter of the Earth, at such a distance, be- 
ing no more than a point. 

As the effect of parallax on a heavenly body is to depress 
it below its true place, it must necessarily affect its right 
ascension and declination, its latitude and longitude. On 
this account, the parallax of the Sun and Moon must be 
added to their apparent altitude, in order to obtain their 
true altitude. 

The true altitude ot the Sun and Moon, except when in the zenith, is always 
affected, more or ler<s, both by parallax and refraction, but always in a contrary 
manner. Hence the mariner, in finding the latitude at sea. always adds the 
parallax, and subtracts the refraction, to ami from the Sun's observed altitude, 
in order to obtain the true altitude, and thence the latitude. 

The principles of parallax are of great importance to as- 
tronomy, as they enable us to determine the distances of 
the heavenly bodies from the Earth, the magnitudes of the 
planets, and the dimensions of their orbits. 

The Sun's horizontal parallax being accurately known, 
the Earth's distance from the Sun becomes known ; and the 
Earth's distance from the Sun being known, that of all the 
planets may be known also, because we know the exact 
periods of their sidereal revolutions, and according to the 
third law of Kepler, the squares of the times of their revolu- 
tions are proportional to the cubes of their mead distances. 
Hence, the first great desideratum in astronomy, where 
measure and magnitude are concerned, is the determination 
of the true parallax. 

At the late council of astronomers, assembled in London, 
from the most learned nations in Europe, the Sun's mean 
horizontal parallax was settled, as the result of their united 

What, (hen, are the neces«ary effects of parallax on the appearance of a heavenly 
body How, then, can we obtain the true altitude of the Suu or Moon? Do para* lax 
and refraction effect the altitude alikei aire an example. Why are th'« principle* 
of parallax of great importance to astronomy If the Sun's parallax be known, how 
mar the distances of nil the planets he known al«o What inference may be derived 
from this in regard to the importance of parallax.' 

27 



314 PROBLEMS. 

observations, at 0° 0' 8".5776. Now the value of radius, 
expressed likewise in seconds, is 206264".8 ; and this di- 
vided by 8".5776, gives 24047 lor the distance of the Sun 
from the Earth, in semi-diameters of the latter. If we take 
the equatorial semi-diameter of the Earth as sanctioned 
by the same tribunal, at (7924-«-2=) 3962 miles, we shall 
have 24047X3962=95,273,869 miles for the Sun's true dis- 
tance. 

Both the principle and the calculation of this element may 
be illustrated by a reference to the diagram on Plate 1 of 
the Atlas: Thus— the parallactic angle AES = 8 // .5776 : 
is to the Earth's semi-diameter as = 3962 miles : : as radius 
= 206264 // .8: is to the distance ES = 95,273,869 miles, as 
before. 

Again : The mean horizontal parallax of the Moon is 
C 57' 11", or 3431". In this problem, the parallactic angle 
AMS is 0° 57' 11"= 3431"; and 3431": is to 3962 miles: : 
as 206264".S: is to 238,161 miles, for the Moon's mean dis- 
tance from the Earth MS. — >S f ee Chapter on the Number 
and Distance of the Stars. 



CHAPTER XXIX. 

PROBLEMS AND TABLES. 



TO CONVERT DEGREES, ETC., INTO TIME. 

Rule 1. — Divide the degrees by 15. for hours; and multi- 
ply the remainder, if any, by 4, for minutes. 

2. Divide the odd minutes and seconds in the same manner 
by 15 for minutes, seconds, &c, and multiply each remainder 
by 4, for the next lower denomination. 

Example 1. — Convert 32° 34' 45" into time. 
Thus, 32° -^- 15 = 2h. 8' 

34 -*. 15= 2 16" 
45 -f- 15 = 3 



Ans. 32°34'45"=2h. 10' 19" the time. 

Example 2. — If it is 12 o'clock at this place, what is the time 
20° east of us? 

Thus, fifteen in 20°, once, and five over ; the once is 1 hour, 
and the 5 multiplied by 4, ajves 20 minutes : "*»e time is then 
I hour and 20 minutes ; i 



PROBLEMS. 315 

Example 3. — The longitude of Hartford is 72° 50' west of 
Greenwich ; what time is it at Greenwich when it is 12 
o'clock at Hartford ? Ans. 4 h. 51 rain. 20 sec- 

Example 4. — When it is 12 o'clock at Greenwich, what is 
the time at Hartford ? Ans. 7h. 8m. 40 sec. A. M. 

Note. — Table VIII. is designed to facilitate calculations of this kind. Tne de- 
grees being placed in one column, and the corresponding time in another, it 
needs no explanation, except to observe that degrees in the left-hand columns 
may be considered as so many minutes, instead oT degrees ; in which case, the 
corresponding time in the adjoining column, must be read as mm«(es and se- 
conds, instead of hours and minutes. In like manner, the degrees in the left- 
hand column may be read as seconds, and the corresponding time, as seconds 
and thirds. 
Example. — Find, by the table, the time corresponding to 32° 34' 45". 
Thus : ' Against 32° is 2 h. 8 min. 

" 34' « 2 16 sec. 

<< 45// u 3 

Answer as above, 2 h. 10 m. 19 s. 



PROBLEM II. 
TO CONVERT TIME INTO DEGREES, ETC. 

Rule. — Multiply the hours by 15, and to the product add 
one fourth of the minutes, seconds, &c, observing that every 
minute of time makes i°, and every second of time, f. 

Example 1. — In 2 hours, 10 minutes, and 19 seconds ; how 
many degrees ? 

Thus : 2 h. 10 m. 19 sec. 

15 

30° 



Add 10 quarters, or J of the min. 2 30' 
Add 19 quarters, or | of the sec. 4 



45" 



Ans. 32° 34' 45" 

This problem is readily solved by means of Table IX. without the labor of 
calculation : 

Thus: 2 hours =30' 

10 minutes = 2 30' 
19 seconds = 4 43" 



Ex. 2.— When it is 12 o'clock at Hartford, it is 4 hours, 51 
minutes, and 20 seconds past noon at Greenwich; how ma- 
ny degrees is Hartford west of Greenwich? 

Thus: 15 times 4 is 60— added to } of 51, is 72° 45'' and 
this increased by i of 20, is 72° 50'. Ans. 

Ex. 3. — A Liverpool packet, after sailing several days from 
New York, finds the time by the Sun 2 hours and 40 mi- 



316 PROBLEMS. 

nutes later than by the ship's chronometer : how far has the 
ship progressed on her way? 

Ex. 4. — A vessel leaves Boston, and having been tossed 
about in foul weather for some days, finds, that when it is 
12 o'clock by the Sun, it is only 11 o'clock and 50 minutes 
by the watch ; is the vessel east or west of Boston ; and 
how many degrees ? 

Ex. 5. — The moment of greatest darkness during the an- 
nular eclipse of 1831, took place at New Haven, 10 minutes 
after 1 o'clock. A gentleman reports that it happened pre- 
cisely at 1, where he observed it; and another, that it was 
5 minutes after 1 where he saw it: Quer'e. How far east or 
west were these gentlemen from each other and how many 
degrees from New Haven 1 

PROBLEM III. 

TO FIND WHAT STARS ARE ON THE MERIDIAN AT NINE O'CLOCK 
IN THE EVENING OF ANY GIVEN DAY. 

Rule. — Look for the given day of the month, at the bottom 
of the maps, and all the stars having the same degree of 
right ascension will be on the meridian at that time. 

Example 1. — What stars will be on the meridian at 9 
o'clock, the 19th of January? 

Solution. — On Plate III. I find that the principal stars 
standing over against the 19th of January, are Rigel and 
Capella. 

Ex. 2. — What stars are on the meridian the 20th of De- 
cember ? Ans. Menkar and Algol. 

PROBLEM IV. 
ANY STAR BEING GIVEN, TO FIND WHEN IT CULMINATES. 

Rule. — Find the star's right ascension in the table, or by 
the map, (on the equinoctial,) and the day of the month at 
the top or bottom of the map will be the day on which it 
culminates at 9 o'clock. 

Example 1. — At what time is the bright star Sirius on the 
meridian ? 

Solution. — I find by the table, and by the map. that the 
right ascension of Sirius is 6 hours and about 38 minutes; 
and the time corresponding to this, at the bottom of the map, 
is the 11th of February. 

Ex. 2. — At what time is Alpheratz. in the head of Andro- 
sieda, on the meridian? Ans. The 9th of November. 



PROBLEMS. 317 

PROBLEM V. 

THE RIGHT ASCENSION AND DECLINATION OF A PLANET BEING 
GIVEN, TO FIND ITS PLACE ON THE MAP. 

Rule. — Find the right ascension and declination of the 
planet on the map, and that will be its place for the given 
day. 

Example 1. — Venus' right ascension on the 1st of Janu- 
ary 1833, was 21 hours. 30 minutes, and her declination 16f° 
south ; required her situation on the map ? 

Solution. — On the right hand of the Plate IT. I count off 
16f° from the equinoctial, on the marginal scale south, and 
from that point, 30 minutes to the left, or just half the dis- 
tance between the XXI. and XXII. meridian of right as- 
cension, and find that Venus, that day, is within two degrees 
of Delta Capricorni, near the constellation Aquarius, in the 
zodiac. 

Note. — It is to be rememberer], that the planets will always be found within 
the limits of the zodiac, as represented in the maps. By means of Table VII. th« 
pupil can find at any time the situations of all the visible planets, on the maps ; 
and this will enable "him to determine their position in the heavens, without a 
chance of mistake. By this means, too. lie can draw for himself the path of the 
planets from month to month, and trace their course among the stars. This is a 
pleasant and usefnl exercise, and is practised extensively in some academies. 
The pupil draws the map in the first place, or such a portion of it as to include 
the zodiacal constellations; then, having dotted the position of the planets trom 
day to day, as indicated in Table VII., their path is easily traced with a pen or 
pencil. 

Ex. 2.— Mars' right ascension on the 13th of March, 1833, 
is 5 hours, 1 minute, and his declination 24f ° north ; requir- 
ed his situation on the map' 2 

Solution. — I find the fifth hour line or meridian of right as- 
cension on Plate III., and counting upwards from the equi- 
noctial 24|°, I find that Mars is between the horns of Tau- 
rus, and about 5° S. W. of Beta Aurigse. 

Ex. 3. — Required the position of Jupiter and Saturn on 
the 13th of February and the 25th of May? 

When the right ascension and declination of the planets arc not given, they axe 
to be sought in Table VII. 

PROBLEM VI. 

TO FIND AT WHAT MOMENT ANY STAR WILL PASS THE MERIDIAN 
ON A GIVEN DAY. 

Rule. — Subtract the right ascension of the Sun from the 
star's right ascension, found in the tables : observing to add 
24 hours to the star's right ascension, if less than the Sun's, 
and the difference will show how many hours the star cul- 
minates after the Sun. 

Example 1. — At what time will Procyon pass the meridi- 
an the 24th of February ? 



318 PROBLEMS. 

Solution— R. A. of Procyon 7h. 30m, 33s.+24h. 

31 30' 33" 
R. A. of Sun, 24th of Feb. 22 20 1 



Ans. 9 1 32 

That is, lm. 32s. past 9 o'clock in the evening. 
Ex. 2.— At what time will Denebola pass the meridian on 
the first of April? 

Solution— R. A. of Denebola is llh. 40' 32" 

R. A. of Sun. April 1, 41 25 

Ans. 10 59 7 

That is, at 59 minutes, 7 seconds, past 10 in the evening 1 . 

Ex. 3. — At what time on the first day of each month, from 
January to July, will Alcyone, or the Pleiades, pass the me- 
ridian ? 

Ex. 4. — At what time will the Dog-Star, or Sirius. culmi- 
nate on the first day of January, February, and March? 

Ex. 5. — How much earlier will Spica Virginis pass the 
meridian on the 4th of July, than on the 15th of May? — 
Ans. 3 hours, 25 minutes. 

PROBLEM VII. 

TO FIND WHAT STARS WILL BE ON OR NEAREST THE MERIDIAN 
AT ANY GIVEN TIME. 

Rule. — Add the given hour to the Sun's right as< onsion, 
found in Table III., and the sum will be the right ascension 
of the meridian, or mid-heaven; and then find in Table II. 
what star's right ascension corresponds with, or comes near- 
est to it, and that will be the star required. 

Example 1. — What star will be nearest the meridian at 
9 o'clock in the evening of the 1st of September ? 
Solution. — Sun's right ascension 1st September, 

lOh 40' 30" 
Add the time from noon 9 



Right ascension of the meridian 19h 40' 30" 

Now all the stars in the heavens which have this right as- 
cension, will be on the meridian at that time. On looking 
into Table II. the right ascension of Altair, in the Eagle, 
will be found to be 19h. 40m. ; consequently Altair is on the 
meridian at the time proposed ; and Delta, in the Swan, is 
less than two minutes past the meridian. 

Ex.2. — Walking out in a bright evening on the 4th of 
September, I saw a very brilliant star almost directly over- 



PROBLEMS. 319 

head ; I looked on my watch, and it wanted 20 minutes of 
8; required the name of the star? 

Solution. — Sun's declination 4th of September, 

lOh 51' 22" 

Add the time from noon 7 40 



Gives R. A. of Lyra, nearly 18 31 22 

Ex. 3. — About 8i minutes after 8 in the evening of the 

11th of February, I observed a bright star on the meridian, 

a little north of the equinoctial, and 1 minute before 9 a still 

brighter one, further south ; required the names of the stars ? 

PROBLEM VIII. 

TO FIND WHAT STARS WILL CULMINATE AT 9 O'CLOCK IN THE 
EVENING OF ANY DAY IN THE YEAR. 

Rule. — Against the day of the month in Table IV., find 
the right ascension of the mid-heaven, and all those stars in 
Table II. which have the same, or nearly the same right as- 
cension, will culminate at 9 P. M. of the given day. 

Example 1. — What star will culminate at 9 in the even- 
ing of the 26th of March ? 

Solution. — I find the right ascension of the meridian, at 9 
o'clock in the evening of the 26th of March, is 9h 19' 37" ; 
and on looking into Table II., I find the right ascension of 
Alphard, in the heart of Hydra, is 9h 19' 23". The star is 
Alphard. 

Ex. 2. — What star will culminate at 9 in the evening of 
the 28th of June ? Ans. Aphacca. 

problem IX. 

TO FIND THE SUN'S LONGITUDE OR PLACE IN THE ECLIPTIC, ON 
ANY GIVEN DAY. 

Rule. — On the lower scale, at the bottom of the Plan 1 ' - 
phere, (Plate VIII.) look for the given day of the month; 
then the sign and degree corresponding to it on the scale 
immediately above it, will show the Sun's place in the 
ecliptic. 

Example 1. — Required the Sun's longitude, or place in the 
ecliptic, the 16th of September. 

Solution. — Over the given day of the month. September 
16th, stands 5 signs and 23 degrees, nearly, which is the 
Sun's place in the ecliptic at noon on that day ; that is, the 
Sun is about 23 degrees in the sign Virgo. 

N. B. If the 5 signs he multiplied hy 30, and the 23 degrees be added to it, it 
will give the longitude in degrees, 173. 



320 PROBLEMS. 

Ex. 2. — Required the Sun's place in the ecliptic at noon, 
on the 10th of March. 



GIVEN THE SUN'S LONGITUDE, OR PLACE IN THE ECLIPTIC, TO 
FIND HIS RIGHT ASCENSION AND DECLINATION. 

Rule. — Find the Sun's place in the ecliptic, (the curved 
line which runs through the body of the planisphere.) and 
with a pair of compasses take the nearest distance, between 
it and the nearest meridian, or hour circle, which being ap- 
plied to the graduated scales at the top or bottom of the 
planisphere, (measuring from the same hour circle.) will 
show the Sun's right ascension. Then take the shortest 
distance between the Sun's place in the ecliptic and the 
nearest part of the equinoctial, and apply it to either the 
east or west marginal scales, and it will give the Sun's de- 
clination. 

Example 1.— The Sun's longitude, September 16th, 1833, 
is 5 signs, 23 degrees, nearly; required hie right ascension, 
and declination. 

Solution. — The distance between the Sun's place in the 
ecliptic and the nearest hour circle being taken in the com- 
passes, and applied to either the top or bottom graduated 
scales, shows the right ascension to be about 11 hours 35 
minutes ; and the distance between the Sun's place in the 
ecliptic, and the nearest part of the equinoctial, being applied 
to either the east or west marginal scales, shows the decli- 
nation to be about 2° 45', which is to be called north, because 
the Sun is to the northward of the equinoctial : hence the 
Sun's right ascension, on the given day, at noon, is about 11 
hours 35 minutes, and his declination 2° 45' N. 

Ex. 2.— The Sun's longitude March 10th, 1833, is 11 
signs, 19 degrees, nearly ; required his right ascension and 
declination ? 

Ans. R. A. 23 h. 21 min. Decl. 4° 11' nearly. 

problem XI. 

TO FIND THE RIGHT ASCENSION OF THE MERIDIAN AT ANY 

GIVEN TIME. 

Rule. — Find the Sun's place in the ecliptic by Problem 
IX. and his right ascension by Problem X., to the eastward 
of which, count off the given time from noon, and it will 
show the right ascension of the meridian, or mid-heaven. 

Example 1. — Required the right ascension of the meridi- 
an 9 hours, 25 minutes past noon, September 16th, 1833- 



PROBLEMS. 321 

Solution. — By Problems IX. and X., the Sun's right as- 
cension at noon of the given day, is 11 hours, 35 minutes ; 
to the eastward of which. 9 hours and 25 minutes (the given 
time) being counted off, shows the right ascension of the 
meridian to be about 21 hours. 

Ex. 2. — Required the right ascension of the meridian at 
6 hours past noon, March 10th. 1833 ? 

Solution. — By Problems TX. and X.. the Sun's right as- 
cension at noon of the given day, is 23 hours and 21 min- 
utes ; to the eastward of which, the given time, 6 hours, 
being counted off. shows the right ascension of the meridian 
to be about 5 hours, 21 minutes. 

Remark.— In this example, it may be necessary to observe, that where the 
eastern, or left-hand extremity of the planisphere leaves off, the western, or right- 
hand extremity begins; therefore, in counting off the given time on the top or 
bottom graduated scales, the reckoning is to be transferred from the left, and 
completed on the right, as if the two outside edges of the planisphere were joined 
together. 

PROBLEM XII. 

TO FIND WHAT STARS WILL BE ON OR NEAR THE MERIDIAN, 
AT ANY GIVEN TIME. 

Rule. — Find the right ascension of the meridian by 
Problem XI., over which lay a ruler, and draw a pencil line 
along its edge from the top to the bottom of the planisphere, 
and it will show all the stars that are on or near the me- 
ridian. 

Example 1. — Required what stars will be on or near the 
meridian at 9 hours, 25 minutes past noon, Sept. 16th, 1333 ? 

Solution. — The right ascension of the meridian by Prob- 
lem XI. is 21 hours: this hour circle, or the line which 
passes up and down through the planisphere, shows that no 
star will be directly on the meridian at the given time ; but 
that Alderamin will be a little to the east, and Deneb Cygni 
a little to the west of it; also Zeta Cygni, and Gamma and 
Alpha in the Little Horse, very near it on the east. 

PROBLEM XIII. 
TO FIND THE EARTH'S MEAN DISTANCE FROM THE SUN. 

Rule. — As the Sun's horizontal parallax is to radius, so 
is the semi-diameter of the Earth to its distance from the 
Sun. 

By Logarithms. — As tangent of the Sun's horizontal par- 
allax is to radius, so is the Earth's semi-diameter to her 
mean distance from the Sun. 

S".577G : 206264".8 : : 3962: 95,273,869 miles. 



g«>2 PROBLEMS. 

By Logarithms. co^/vr 

As tanzent of the Sun's- horizontal parallax, 8".5776 - J-gggw 
Is to radius, or 90°, . - w „^ 

So is the Earth's semi-diameter, 3962. = *5W91« 

To the Earth's distance, 9o,273,S69 - 7.97s9733 



PROBLEM XIV. 

TO FIND THE DISTANCE OF ANY PLANET FROM THE SUN, THAT 
OF THE EARTH BEING KNOWN. 

Rule— Divide the square of the planet's sidereal revolu" 
tion round the Sun, by the square of the Earth's sidereal 
revolution, and multiply the cube root of the quotient by the 
Earth's mean distance from the Sun. 

Bu Logarithms.— From twice the logarithm of the plan- 
et's sidereal revolution, subtract twice the logarithm of the 
Earth's sidereal revolution, and to one third of the remain- 
der, add the logarithm of the Earth's mean distance from 
the Sun. 

EXAMPLE.-Required Mercury's mean distance from the Sun, that of the Earth 
^^S^6S^evolnt\on^m.9^S^jB,or 76CK)M3».89I2 : ,he Earth's 

sidereal revolution is 365256374417 days, or 

31558151". 5 -EJgSo q 

3155815l".5 ,tmAo.9 

905916962096952.25 by which divide 57768267575827.21 w _ 

and tl.e quo ient will be .052005106713292, the cube root of which is 0.3870977, 
»nH h?<S inlied by 94 881,891, gives 36.727,607 miles, for Mercury's distance 
from the Sun P This ^robtmma; be performed by logarithms m as many mm. 
utes as the former method requires J' "™^-,.- V9 13 76 lCS94 

§)-2. 7634290 






1.5878097 
Add. log. of the Earth's mean distance, 7.9 /89/33 

*T&7vurtte'e™f*& learnedVhe use of logarithms this : proble^U 

tmer Shod^ he come to the true result in five hours ; nor remarkably qu.ck, 
if by the latter he come to it in five minutes. 

PROBLEM XV. 

TO FIND THE HOURLY MOTION OF A PLANET IN ITS ORBIT. 

Rule.— Multiply the planet's mean distance from the Sun 
bv 6 2831853, and divide the product by the time ot me 
planet's sidereal revolution, expressed in hours, and tne 
decimals of an hour. 



PROBLEMS. 323 

By Logarithms.— Add 0.79S 1799 to the logarithm of the 
planet's mean distance from the Sun, and from the sum 
subtract the logarithm of the planet's revolution expressed 
in hours. 

Example.— Required the Earth's hourly motion iu its orbit. 
Log. of Earth's distance = 7. 9789733+0. 79SL7.99 = 8.7771537 

Subtract log. of Earth's revolution 3.9428090 

Gives Earth's horary motion, 68.283 miles, 4.5343447 

PROBLEM XVI. 
TO FIND THE HOURLY MOTION OF A PLANET ON ITS AXIS. 

Rule. — Multiply the diameter of the given planet by 
3.14159, and divide the product by the period of its diurnal 
rotation. 

By Logarithms. — Add 4.0534524 to the logarithm of the 
planet's diameter, and from the sum subtract the logarithm 
of its diurnal rotation, expressed in seconds. 

Earth's diameter. 7924 log. = 3.S9S9445 

A.dd log. of 3600" — - log. of 3.14159 = 4.0534524 



■Subtract log. diurnal rotation, 23h. 50' 4".09 = 4.9353263 

Ans. 1040.09 miles => 3.0170706 

PROBLEM XML 
TO FIND THE RELATIVE MAGNITUDE OF THE PLANETS. 

Rule. — Divide the cube of the diameter of the larger 
planet by the cube of the diameter of the less. 

By Logarithms. — From three times the logarithm of ".he 
larger, subtract three times the logarithm of the less. 

Example.— How much does the size of the Earth exceed that of the Moon] 
Earth's diameter, 7912 losr. 3.8932863X3 - U.694S5S9 

Moon's diameter. 2160 lo ? . 3.3343376 X-3 - 10.0030123 

The Earth exceeds the Moon, 49.1865 times. Ans. 1.6918461 

In this example. 7912 miles is assumed as the mean between the Eirth's 
equatorial arid "polar diameter: the former being 7924, and the latter 7S9S 
miles. 

PROBLEM XVIII. 

TO FIND THE PROPORTION OF SOLAR LIGHT AND HEAT AT 
EACn OF THE PLANETS. 

Rule. — Divide the square of the planet's greater distance 
from the Sun. by the square of the less. — Or. subtract 
twice the logarithm of the greater distance from twice the 
logarithm of the less. 



324 PROBLEMS 

Example. — How much greater is the Sun's light and heat 
at Mercury, than at the Earth ? 



Log. of Earth's distance 

— of Mercury's 

Ans. 6.6736 times greater = 



7.9789733X2 = 15.9579476 

7.5667959X2 = 15.1335918 

0.824355* 



PROBLEM XIX. 



TO FIND THE CIRCUMFERENCE OF THE PLANETS. 

Rule. — Multiply the diameter of the planet by 3.14159, or, 
add the logarithm of the planet's diameter to 0.4971499. 

PROBLEM XX. 

TO FIND THE CIRCUMFERENCE OF THE PLANETARY ORBITS. 

Rule. — Multiply the planet's mean distance from the Sun 
by 6.2S31853; or, to the logarithm of the planet's mean dis- 
tance, add 0.7981799, and the sum will be the logarithm of 
the answer. 

PROBLEM XXI. 



TO FIND IN WHAT TIME ANY OF THE PLANETS WOULD FALL TO 
THE SUN, IF LEFT TO THE FORCE OF GRAVITATION ALONE. 

Rule. — Multiply the time of the planet's sidereal revolu- 
tion, by 0.17677b; the result will be the answer. 

By Logarithms. — From the logarithm of the planet's si- 
dereal revolution, subtract 0.7525750. and the remainder will 
he the logarithm of the answer, in the same denomination 
as the sidereal revolution. 

Required the times, respectively, in which the several planets would fall to th* 
Sun by the force of gravity. 



Planets would fall to 
the Sun. 


Days. 


II. 


M. 


s. 


Logarithms. 


Mercury. 




15 


13 


13 


16 


(.1289686 


Venus, 




39 


17 


19 


22 


6.5355424 


Earth, 




64 


IS 


3fl 




6 7466367 


Mars, 




121 


10 


36 


3 


7,0406 


Jupiter, 




765 


21 


3'! 


35 


7.8996849 


Saturn, 




1901 


n 


•■•4 


4 


8.2157 ISti 


Herschel. 




5424 


is 


62 


1 


8.6703897 


Moon to the Earth, 


4 


19 


64 


57 


5.6204459 



Sun, 

Mercur 

Venus, 

Earth, 

Mars, 

Vesta, 

Juno, 

Ceres, 

Pallas, 

Jupiter, 

Saturn, 

llersch 


3 

3 

3 


Mercur 

Venus, 

Earth, 

Mars, 

Vesta, 

Juno, 

Ceres, 

Pallas, 

Jupiter, 

Saturn, 

Herschi 


r 15 


™ ^ 






re O 




5 




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TABLE I. 

Uon tuning the names of the Constellations, the number and magnitudt 
of tae Stars in each, and the days on which they come to the mend- 
ian it 9 o'clock in the evemig. 



April. 



May. 



Eridanus, 

Reticulus, 

Taurus, 

Brandenburgh Sg» ptre, 

Praxiteles, 

Carnelopard, 

Auriga, 

feword Fisfi, 

Moris Mens*, 

Lepus, the Hare, 

Orion, 

Painter's Horse, 

Noah's Dove, 

Canis Major, 

Monoceros, 



July. 



The Lynx, 

Argo Navis, 

Canis Minor, 

Flying Fish, 

Can:er, 

Mariner's Compass, 

Hydra, 
. Sextans, 
6 Leo Minor, 
6 Leo Major, 
6 Air Pump. 
" Ursa Major, 

Robur Carroll, 

Crater, the Cup, 

Chameleon, 

The Cross, 
. Coma Berenices, 
\3 Corvus, the Crow, 

Southern Fly, 

Cor Caroli, 

Virgo, 

Asierion et Chara, 

Centaurus, 

Bootes, 

Compasses. 
-. Mons Msenalus, 
22 libra, 

Lupus, the Wolfj 

Corona Borealia 

I rsa Itfinor, 



R. A. 


Decu 


No. of 


Magnitudes. 




Stars. 










1 


2 


III 


5 1 6 


60° 


10° S. 


84 


1 


1 


ll|27 


20 57 


62 


62 


S. 


10 








2 


3 


2 5 


65 


it; 


N. 


141 


1 


1 


4 


S 


23 GO 


67 


15 


s. 


3 










i 


68 


40 


s. 


16 














4 1 18 


63 


70 


N 


58 











6 


25 


12 


75 


4S 


N. 


66 


1 


1 


t 


9 


20 


2b 


75 


62 


8 


6 








1 


1 


4 


24 


76 


72 


8. 


30 





(I 


[ 








30 


80 


13 


8. 


19 








3 


7 


3 


13 


80 







78 


2 


4 


3 


15 


18 


36 


84 


55 


8 


8 











1 





39 


85 


35 


s. 


10 





1 


] 


2 


4 


63 


105 


20 


8 


31 


t 


4 


2 


7 


7 


3h 


no 







31 











1 


7 


12 


in 


32 


N 


85 





2 


3 


6 


13 


21 


in 


50 


N. 


44 











3 


15 


•J.5 


115 


50 


s. 


64 


2 


4 


9 


12 


37 


289 


112 


5 


N. 


14 


1 





1 





3 


9 


127 


68 


8. 


8 














6 


8 


126 


20 


N. 


83 











3 


8 


11 


130 


H) 


8 


4 














2 


13 


139 


s 


8 


60 





i 





13 


16 


45 


150 







41 











\ 


6 


36 


150 


r> 


N. 


53 








1 




10 


39 


150 


15 


N. 


95 


1 


1 


G 


15 


12 


« 


150 


',2 


s. 


3 
















13 


153 


60 


N. 


87 


1 


3 


7 


13 


$1 


37 


159 


50 


g 


12 














1138 


5 


s. 


31 











10 





14 


175 


78 


8. 


10 














6 


25 


135 


;o 


S : 


5 


1 


■•> 


1 


1 


1 


12 


1S5 


X 


N. 


43 











13 


13 


17 


185 


15 


s 


9 








3 


2 


2 


2 


185 


58 


8. 


5 











4 





17 


191 


39 


N. 


3 














195 


5 


N 


110 


1 





c 


10 


16 


71 


200 


10 


N 


25- 








1 


I 


7 


15 


200 


50 


8 


35 


2 


1 


6 


10 


11 


IO0 


212 


20 


N. 


54 


1 





7 


10 


H 


30 


222 


54 


8 


4 








1 


1 


a 


225 


5 


N. 


11 














220 


8 


8 


51 





2 


3 


12 


4 


27 


230 


45 


8 


24 








3 


3 


18 


a 


235 


30 


N. 


21 





1 


1 


5 


9 


5 


235 


75 


N. 


24 





1 


2, 


4 


6 


4 









TABLE L— 


Continued. 
















1 


Month 




Constellations. 


R. A. 


Decli- 


No. of 
Stars. 


Magnitudes 


£ 




1 










1 



2 

1 


3 

9 


4 


Hi 


49 


July. 


The Serpent, 


235° 


10° N. 


64 


3i4t 


Si 




4 


S. Triangle, 


238 


65 


S. 


5 





1 


2 


? 


l'lti 


51 




5 


EucliJ.'s~Square, 


242 


45 


s. 


12 














3 26 


52 




lLi 


Scorpio, 


244 


26 


s. 


44 


1 


1 


11 


10 


4!29 


53 




15 


Bird of Paradise, 


252 


75 


s. 


11 














216 


54 




21 


Ara, the Altar, 


255 


55 


s. 


9 








3 


3 


1;30 


55 




21 


Hercules, 


255 


22 


N. 


113 





1 


5 


19 


36! 46 


56 




Serpentarius. 


260 


13 


N. 


74 





1 


5 


10 


9 42 


57 


August 


8 


Draco, 


270 


66 


N. 


80 





4 


7 


12 


: ! 5 .,-, 


55 




6 

10 


Cerberus, 
Scutum Sobieski, 


271 

275 


22 
10 


N 

s. 














1 














60 




10 


Taurus Poniatowski, 


275 


7 


N 


16 











3 


1!12 


01 






Corona Australia, 


278 


40 


S. 


12 














5j 10 


62 




13 


Telescopium, 


278 


40 


s. 


9 











3 


6:30 


63 




19 


Lyra, the Harp, 


2S3 


33 


N. 


21 


1 





2 


2 


6 12 


6} 




21 


Sagittarius, 


285 


33 


S. 


69 








5 


10 


12J59 

o'is 


65 




29 


Amino us, 


292 

















66 


Sept. 


1 


Sagitta, 


295 


13 


N. 


IS 











4 




67 




1 


Aquila, 


295 


8 


N. 


71 


1 





9 


7 


14 33 


63 




6 


Fox and Goose, 


300 


25 


N. 


35 











5 


13 21 


69 




9 


The Peacock, 


302 


65 


S. 


14 





1 


2 


3 


4 


50 


70 




15 


Delphinus, 


308 


15 


N. 


13 








5 


1 


2 


11 


71 




Is 


Cygnus, 


303 


42 


N. 


81 





1 


6 


11 


16 


49 


72 




15 


Capricorn, 


310 


20 


S. 


51 








3 


3 


7 


4 


73 




15 


Hadley's Qnadrarv* 


310 


50 


S. 


43 








1 





6 64 


71 




_ 


Microscopium, 


315 


35 


s. 


10 














lilt 


75 




•2.3 


The Indian, 


315 


55 


s. 


12 








1 


1 


2 54 


76 




■ 


Equulus, 


316 


5 


N: 


10 











4 


1 5 


77 


Oct. 


10 


The Crane, 


330 


45 


S. 


13 





1 


2 


2 


64i 


75 




15 


Aquarius, 


335 


14 


s. 


103 








4 


7 


23,59 


"9 




15 


Southern Fish 


335 


30 


s. 


24 


1 





2 


5 


9 


19 


90 




16 


The Lizard, 


336 


43 


N. 


16 











3 


7 


7 


51 




15 


Cepheus, 


333 


63 


N. 
















52 




20 


Pegasus, 


340 


14 


N. 


89 





3 


3 


9 


14 


51 


63 


Nov. 


9 


American Goose, 


359 


6^ 


s. 


,9 








1 


2 


5 


53 


Si 




13 


Oflicina Sculptoria 


3 


33 


4; 


12 














5 


29 


So 




15 


Pisces, 


5 


10 


n' 


113 








13 


5 


28 


03 


n; 




20 


Phcenix, 


10 


50 


s. 


13 





1 


] 


3 


763 


57 




22 


Cassiopeia, 


12 


GO 


N. 


55 








5 


6 


833 


5-5 




23 


Andromeda, 


14 


30 


N. 


66 





3 


2 


12 


15 


34 


5 j 


Dec. 


4 


Cetus, 


25 


12 


s. 


97 





2 


9 


10 


11 


GO 


96 




6 


Triangulum, 


27 


32 


N. 


16 











3 


1 


7 


91 




6 


Hydrus, 


28 


66 


S. 


10 








2 


3 


2 


38 


92 






Aries, 


30 


22 


N 


66 





1 


1 


2 


6 


22 


93 




10 


Triangulum Min. 


22 


23 


N. 


5 














94 




17 


Horologiuin, 


40 


55 


S. 


12 














2 


39 


95 




17 


Musca, 


42 


23 


N 


4 








1 


2 


1 




96 




19 


Chemical Furnaco, 


44 


30 


S. 


14 














2 


43 


97 




21 


Caput Medusae, 


44 


40 


N 
















« 




23 


Perseus, 


46 


49 


N. 


59 





2 


4 


10 


M 


31 



TABLE II. 

Exhibiting the Right Ascension and Declination of the principa . 

Fixed Stars, and the time of their coming to the Meridian. 

Those to which S is aunexed are in South declination ; the others are in North 

declination. 






Names of the Stars. 


tr, 
S 


Right 
Ascension. 


Declination. 


On the 
Merid. 




1 


• Persei, 


3 


ii. 
3 


M. 

47 


s. 

8 


o 
39 


31 


37 


Jan. 


i 


2 


y Eridani, 


3 


3 


50 


15 


13 


59 


4S. 




2 


3 


o Eridani, 


3 


4 


3 


31 


7 


16 


32S. 




5 


4 


t Tauri, 


3 


4 


18 


52 


18 


8 


18 




8 


5 


a. Tauri, Aldebaran, 


1 


4 


26 


21 


16 


10 


4 




10 


6 


fi Eridani, 


3 


4 


39 


35 


5 


18 


OS. 




13 


7 


a Aurigae, Capella, 


1 


5 


4 


22 


45 


49 


10 




19 


8 


# Orionis, Rigel, 


1 


5 


6 


31 


8 


23 


55S. 




20 


9 


Tauri, El Nath, 


2 


5 


15 


44 


28 


27 


39 




22 


10 


» Orionis, 


3 


5 


15 


36 


o 


33 


17S. 




22 


11 


y Orionis, Bellatrix, 


2 


5 


16 


11 


G 


11 


32 




22 


12 


Leporis, Nibal, 


3 


5 


21 


22 


20 


53 


46S. 




23 


13 


f Orionis, Mintaka, 


o 


5 


23 


29 





25 


39S. 




24 


14 


* Leporis, Arneb, 


3 


5 


25 


33 


17 


56 


50S. 




24 


15 


• Orionis, Anilam, 


2 


5 


27 


44 


1 


18 


49S. 




25 


HJ 


'C Tauri, 


3 


5 


27 


53 


21 


2 


7 




25 


17 


\ Orionis, Alnitak, 


2 


5 


32 


20 


2 


2 


9S. 




26 


18 


* Columbae, Phaet, 


2 


5 


33 


9 


34 


10 


2S. 




26 


19 


X Orionis, Saiph. 


3 


5 


39 


29 


9 


44 


2S. 




27 


•20 


y2 Columbae, 


3 


5 


45 


6 


35 


50 


12S. 




29 


21 


st Orionis, Betelguese 


1 


5 


46 


8 


7 


22 


6 




29 


22 


yS/SAurig^Menkalina 


2 


5 


47 


17 


44 


55 


24 




29 


23 


.-« r+eminorum, Tejat, 


34 


6 


4 


54 


22 


23 


1 


Fet. 


~i 


24!/" urcminorum, 


3 


C 


12 


54 


22 


35 


48 




4 


25 ! £ Canis Majoris, 


3 


G 


14 


4 


29 


59 


36S. 




5 


2G0 Ca. Maj., Mirzam, 


2 


6 


15 


23 


17 


52 


41S. 




5 


27 


* Navis, Canopus, 


1 
3 


6 


20 


15 


52 


36 


23S. 




6 


28 


y Gemino., Alhena, 


6 


28 


4 


16 


32 


18 




8 


29 


* Canis Maj., Sirius. 


1 





37 


47 


16 


29 


27S. 




11 


30 


e Cams Maj. .Adhara, 


3 


6 


53 


14 


28 


44 


55S. 




31 


£ Geminorum. 


3 


6 


53 


53 


20 


48 


36 




15 


32 


y C. Maj., Muliphen, 


3 


6 


56 


26 


15 


23 


20S. 




lb 


33 <f C. Majoris, Wesen, 
34!^ Gemino., Wasat, 


3 




1 


17 


26 


7 


53S. 




17 


3 


7 


10 


8 


22 


17 


6 




19 


35 


t Argo Navis. 


3 


7 


11 


7 


36 


48 


7S. 




1^ 


30 


« C Maj., Aludra, 


3 


7 


17 


16 


28 


58 


50S. 




21 


37 


at Gemino., Castor, 


2 


7 


23 


56 


32 


14 


52 




23 


& 


ct C. Minor, Procy on, 


1 


7 


30 


33 


5 


38 


55 




24 


39 


/ Ar. Navis, Markab, 


3 


7 


32 


17 


26 


26 


22S. 




25 


ii) 


ii. Gemino., Pollux, 


•j 


7 


35 


5 


28 


25 


28 




* 



TABLE II.— Continued. 



6 


Names of the Stars. } 


£ 

s 


Right 1 Declination> 
Ascension. l ^^ liLia - u 


On the 
Merid. 










H. 


M. 


s. ° 




















42 


? Argo Navis, 


3 


7 


42 


20 24 


26 


35S. 


Feb. 


28 


li 


I Argo Navis, Naos. 


2 


7 


57 


44 39 


32 


3S. 


Mar. 


4 


43 


y Argo Navis, 


2 


8 


4 


23 46 


50 


43S. 




5 


44 * Argo Navis, 


2.3 


8 


19 


5 58 


58 


33S. 




9 


45 A Argo Navis, 


2.3 


8 


40 


7 54 


5 


43S. 




15 


46 / Ursae Majoris, 


3 


8 


47 


47 48 


41 


50 




17 


47 x Cancri, Acubens, 


3.4 


8- 


49 


45 12 


30 


9 




18 


48 \ Argo Navis, 


2.3 


9 


1 


51 42 


45 


40S. 




21 


gP A. N.,Maia Placid. 


1 


9 


12 


57 69 


1 


54S. 




24 


50-/: Argo Navis, 


2.3 


9 


16 


59 54 


17 


53S. 




25 


51 * Hydras, Alphard, 


2 


9 


19 


23 7 


56 


14S. 




26 


52 6 Ursa? Majoris, 


3 


9 


21 


47 53 


26 


45 




27 


53 
51 


2 Leonis, 


3 


9 


36 


22 24 


32 


26 




31 


« Leonis, RasalAsad. 


3 


9 


42 


56 26 


47 


32 


April. 


1 


55 n Leonis, 


3.4 


9 


58 


13 17 


34 


34 




6 


56 


* Leonis Regulus, 


1 


9 


59 


28 12 


46 


52 




6 


57 


K Ursae Majoris, 


3 


10 


6 


58 43 


44 


49 


58 


^ Leonis, Aldhafara, 


3 


10 


7 


23 -24 


14 


53 


59 


^ LeonisJ Al Gsba, 


2.3 


10 


10 


45 20 


41 


16 


9 


CO 


^ U. M., F Phekrah, 


3 


10 


11 


55 42 


20 


15 


! 9 


61 


a Leonis Minoris, 


3 


10 


28 


47 32 


50 


39 14 


€•2 


9 Argo Navis, 


2.3 


10 


37 


12 63 


31 


14S. 


li) 


63|» Argo Navis, 


2 


10 


38 


36 58 


48 


34S. 


i 17 


64 a Crateris, Alkes, 


3,1 


10 


51 


35 17 


24 


36S. 


20 


65 # Ursae Maj., Merak, 


2 


10 


51 


42 57 


16 


35 


;20 


G6 * Ursae Mai., Dubhe, 


2 


10 


53 


21 62 


39 


3 




21 


67 / Leonis, Zozma, 


3 


11 


5 


13 21 


27 


32 




24 


68 9 Leonis, 


3 


11 


5 


39 16 


20 


39 




24 


69 
70 


\ Draconis, Giansar, 


3 


11 


20 


17 


70 


15 


3 




28 


& Leonis, Denebola, 


2 


11 


40 


32 


15 


30 


22 


May. 


1 


71 !,J Virginis, Zavijava, 


3 


11 


42 





2 


42 


43 




3 


72 
73 


y V. Maj., Phach'd, 


2 


11 


45 


1 


54 


37 


25 




4 


<T Centauri, 


2.3 


11 


59 


44 49 


30 


15S. 




t 


74 cT Crucis, 


3 


12 


6 


21 57 


32 


4S. 




lo 


75|cT Ursa? M., Megrez., 


3 


12 


7 


7 57 


58 


46 




10 


76 \y Corvi, 


3 


12 


7 


38 


16 


36 


42S. 




10 


77* Crucis, 


1 


12 


17 


23 


62 


10 


26S. 




13 


78J^ Corvi, Algorab, 


3 


12 


21 


38 


15 


34 


49S. 




14 


79 y Crucis, 


2 


12 


21 


56 


56 


10 


22S. 


iH 


80 


£ Corvi, 


31 


12 


25 


39 


22 


28 


9S. 




Ift 



TABLE II.— Continued. 



c 
2, 


Names of the Stars. 




Right 
Ascension. 


Declination. 


On the 
Merid. 


5 
(3 


81 


^ Draconis, 


3 


H. 

12 


M. 

26 


s 
23 


o 

70 


42 


38 


May. 


15 


82 


y Centauri, 


2.3 


12 


32 


23 


48 


2 


23S. 




16 


83 


y Virginis, 


3 


12 


33 


37 





31 


55S. 




17 


84 


Crucis, 


2 


12 


38 


3 


58 


40 


27S. 




18 


H5 


f Ur. Majoris,Aiioth, 


2 


12 


46 


27 


57 


52 


5 




20 


8(i 


S Virginis, 


3 


12 


47 


12 


4 


18 


31 




20 


87 


a Cor-Caroli, 


3 


12 


47 


57 


39 


13 


21 




20 


HS 


« Vir., Vindemiatrix, 


3 


12 


56 


36 


11 


51 


32 




22 


89 


y Hydroe, 


3 


13 


9 


42 


22 


17 


9S. 




2t5 


90 


' Centauri, 


3 


13 


10 


48 


35 


49 


49S. 




20 


91 


* Virginis, Spica, 


1 


13 


16 


24 


10 


17 


10S. 




27 


92 


K Ursa? Maj., Mizar, 


2 


13 


17 


11 


55 


17 


59 




28 


93 


£ Virginis, 


3 


13 


25 


36 





15 


43 




30 


91 


t Centauri, 


2.3 


13 


29 


20 


52 


32 


20S. 




31 


95 


» U. M., Benetnasch, 


2 


13 


40 


57 


50 


8 


58 


June. 


o 


96 


<f Centauri, 


3 


13 


45 


11 


46 


27 


37S. 




3 


97 


» Bootis, 


3 


13 


46 


32 


19 


14 


39 




4 


98 


Centauri, 


1.2 


13 


52 


8 


59 


33 


36S. 




5 


99 


a Draconis, Thuban, 


3 


13 


59 


52 


05 


10 


31 




7 


100 


a Bootis, Arcturus, 


1 


14 


8 


3 


20 


3 


21 




8 


101 


* Centauri, 


2.3 


14 


24 


54 


41 


25 


OS. 




13 


102 


> Bootis, Seginus, 


3 


14 


25 


17 


39 


2 


32 




13 


103 


* Centauri, 


1.2 


14 


28 


58 


GO 


9 


28S. 




14 


104 


* Lupi, 


3 


14 


30 


40 


46 


39 


47S. 




11 


105 


M Bootis, Mirac, 


3 


14 


37 


41 


27 


47 


2 




16 


IOC. 


* Librae, Zubenesch, 


2.3 


14 


41 


27 


15 


20 


29S. 




17 


107 


& U. Mino., Kochah, 


3 


14 


51 


16 


74 


50 


17 




19 


108 


Bootis, Nekkar, 


3 


14 


55 


12 


41 


3 


18 




20 


109 


Librae, Zubenelg, 


2.3 


15 


8 


2 


8 


45 


41S. 




23 


110 


i Serpentis, 

* C. Bor., Alphacca, 

/ Serpentis, Unuk, 


3 


15 


26 


32 


11 





14 




28 


111 


2 


15 


27 


37 


27 


16 


55 




28 


112 


2 


15 


36 


3 


6 


57 


24 




30 


I I'd 


Serpentis, 


3 


15 


38 


29 


16 


57 


7 


July. 


1 


111 


• Serpentis, 


3 


15 


42 


36 


6 


59 


7 




2 


115 


y Serpentis, 


3 


15 


48 


20 


16 


12 


59 




3 


UGitt Scorpii, 


1 


15 


48 


4 


25 


37 


US. 




3 


117 J Scorpii, 


3 


15 


50 


28 


22 


8 


18S. 




4 


lL9|/3 Scorpii, 


2 


15 


55 


4-1 


19 


20 


28S. 




5 


119 


Draconis, 


1 


15 


58 


37 


59 





32 




G 



TABLE II.— Continued 



>5 Names of the Stars. 




Right 
Ascension. 


Declination. 


On the 

Merid. 


- 


; 




H. 


M. 


s. 


o 


, 








120 «T Ophiu.,Yed,orJed. 


? 


16 


5 


36 


3 


15 


18S. 


July. 


7 


121 • Ophiuchi, 


3 


16 


9 


39 


4 


16 


37S. 




8 


122|> Hercules, 


3 


16 


14 


23 


19 


33 


1 




9 


123 a Scorpii, Antares, 


J 


Hi 


19 


10 


26 


3 


7S. 




11 


124ja Draconis, 


3 16 


24 


12 


61 


53 


38 




11 


125 Hereules,Rutilicus, 


3 16 


23 


22 


21 


57 


36 




12 


126 "I Ophiuchi, 


3 


16 


27 


45 


10 


13 


153.' 


13 


1271* Triang. Australis, 


2.3 


16 


31 


3 


GS 


42 


23S.| 


14 


128 I Herculis, 


3 


16 


34 


59 


31 


54 


39 | 


15 


129 t Scorpii, 


3 


16 


39 


4 


33 


58 


40SJ 


16 


130 u. 1 Scorpii, 


3 16 


40 


8 


37 


45 


14S.I 


16 


131 ? Scorpii, 


3|l6 


42 


52 


41 


3 


33SJ 


17 


132 t Herculis. 


3 16 


54 


14 


31 


10 


40 




19 


133 „ Ophiuchi, 

134* Her., Ras Algethi, 


2.3:17 





50 


15 


30 


35S. 




21 


2.3J17 


; 


2 


14 


35 


17 




23 


135 J- Herculis, 


317 


8 


20 


25 


2 


43 




23 


13G ? Draconis, 
137 ; Aras, 


3 17 


8 


23 


65 


55 


12 




23 


3 


17 


18 


57 


49 


43 


543. 




21 


138 - Scorpii, Lesath, 

139 Q Scorpii, 


2.3 


17 


22 


58 


36 


58 


24S. 


27 


3 


17 


25 


20 


42 


52 


55S.; 


27 


140 * Ophiu., Ras Alhag. 


2 


17 


28 


11 


12 


41 


20 




28 


141/2 Ophiuchi, Cheleb, 


3 


17 


35 


36 


4 


38 


40 




30 


142 y Ophiuchi, 


3 


17 


39 


56 


o 


46 


42 




31 


143 y Draconis. Rastaben, 


2.3 


17 


52 


44 


51 


30 


42 


Aug. 


1 


144 y 2 Sagittarii, 


3 17 


55 


5 


30 


24 


40S. 




4 


145 tT Sagittarii, 


3 18 


10 


1 


29 


53 


2SS. 




8 


146 t Sagittarii, 


2.3118 


12 


48 


34 


27 


MS. 




8 


147 * Lvrae, Vega, 

148 7 Ursoe Minoris, 


3'TT 


26 

28 


11 

6 


38 


38 







12 


35 


47 




12 


149 Lyrce, 


2.3 


18 


43 


55 


33 


10 


33 


17 


150 *" Sagiitarii, 


2 


18 


44 


58 


26 


29 


423. 


17 


1519 Serpentis, Alga, 


3 


IS 


47 


36 


3 


59 


20 




18 


152/ Lyrce, 


3 


18 


49 


6 


36 


41 


28 




18 


153 I Sagittarii, 


3 


18 


52 


1 


30 


6 


40S. 




19 


154 y Lyrce, Jugum., 


3 18 


52 


11 


32 


27 


47 




19 


155* Aquilce, 


3'l8 


52 


26 


14 


50 


4 




19 


156 I A., Deneb e Okab, 


3J18 


57 


44 


13 


37 


20 




20 


157; w Sagittarii, 


3|18 


59 


54 


21 


16 


56S. 




I58j* Sagittarii, 


3.4:19 


12 


19 


40 


55 


9S.i 24 


159/ Draconis, 


3! 


19 


12 


29 


67 


21 


59 ' 




24 



TABLE II.— Continued. 



6 


Names of the Stars. 


to 

a 

a 

3 


Right 
Ascension. 


Declination. 


On the 
Merid 


Q 


1G0 


/ Aquilee, 


H. 

19 


M. 

17 


s 
5 


2 


46 


57 


Aug. 


26 


161 {0 Vulpeculoc, 


3.4 


19 


21 


20 


24 


20 


5 




27 


162!/? Cygni, Albireo, 


3 


19 


24 


17 


27 


36 


51 




28 


163 
164 


y Aquilce, Tarazed, 


3 


19 


38 


19 


10 


12 


48 




31 


«T Cygni, 


3 


19 


40 





44 


43 


25 


Sept. 


1 


165j* Aquilee, Altair, 


1.2 


19 


42 


38 


8 


26 


2 




1 


166;$ Aquilae, Alshain, 


3 


19 


47 


7 


5 


59 


47 




3 


167.6 Aquiloe, 


3 


20 


2 


38 


1 


18 


39S. 




7 


168 * 1 Capri., Dshabeh, 


3 


20 


8 


23 


13 


1 


59S. 




9 


169 U 2 Capricorni, 


3 


20 


8 


47 


13 


3 


16S. 




9 


170 !/3 Capricorni, Dabih, 


•3 


20 


11 


48 


15 


18 


15S. 




10 


171jst Pavonis, 


1.2 


20 


12 


23 


57 


15 


42S. 




10 


172> Cygni, Sa'dr, 


3 


20 


16 


11 


39 


43 


32 




11 


173|j Delphini, 


3 


20 


25 


32 


10 


44 


29 




13 


174/3 Delphini, Rotanen, 


3 


20 


29 


29 


13 


59 


53 




15 


175L Delphini, Scalovin, 


3 


20 


31 


53 


15 


59 


32 




15 


176 j Delphini, 


3 


20 


35 


29 


14 


28 


53 




16 


177|st Cygni, Deneb, 


1.2 


20 


35 


45 


44 


41 


15 




16 


178 > Delphini, 


3 


20 


38 


29 


15 


31 


47 




17 


179 > Cygni, Gienah, 


3 


20 


39 


16 


S3 


20 


16 




17 


18Q£ Cygni, 


3 


21 


5 


22 


29 


32 


45 




25 


181 j* Cephei, Alderamin, 


3 


21 


14 


35 


01 


52 


45 




27 


182/3 Aquarii, 


3 


21 


22 


46 


6 


18 


9S. 




29 


183 !£ Cephei, Alphirk, 


3 


21 


26 


28 


69 


49 


43 


Oct. 


2 


184 \y Capricorni, 


3 21 


30 


45 


17 


24 


48S. 




3 


185* Pegasi,Enif, 


2.3 21 


35 


32 


9 


6 


47 




4 


186 


sT Capricorni, 


3 


21 


37 


49 


16 


52 


33S. 




9 


18? 


* Aquarii, 


3 


21 


57 


12 


1 


7 


33S. 




9 


188 


a Gruis, 


2 


21 


57 


40 


47 


45 


38S. 




11 


189 


K Cephei, 


3 


22 


5 


5 


57 


22 


59 




13 


190 


y Aquarii, 


3 


22 


12 


38 


2 


13 


40S. 




16 


191 


$ Piscis Australis, 


3 


22 


21 


50 


33 


11 


44S. 




18 


192,* Piscis Australis! 


322 


31 


49 


27 


54 


48S. 




19 


193 


£ Pegasi, 


3 22 


33 


36 


9 


57 


49 




22 


194 


f Aquarii, Scheat, 


3 


22 


45 


43 


26 


42 


3 IS" 




23 


195 


* Pise. Aust.,Fomalh. 


1 


22 


48 


24 


30 


30 


18S. 




24 


196 


$ Pegasi, Scheat, 


2 


22 


55 


32 


27 


10 


27 




25 


197 


n Pegasi, Markab, 


o 


22 


56 


27 


14 


18 


37 


Nov. 


3 



TABLE II.— Continued. 



6 


Names of the Stars. 




AsSn. D ^^ 


On the 
Mend. 


rj 








a 


M 


*. J O 


- 


" 




m 


y Cephei, Er Rai, 


3 23 


32 


16 76 


41 


52 


Nov. 


10 


199 


* Andromeda, A] ph.. 


o 


23 


59 


46 28 


10 


9 




10 


200 -^ Cassiopeia, Chaph, 


3 24 





36 58 


13 


47 




11 


201 y Pegasi, Algenib, 


3 





4 


39 14 


15 


22 




14 


202 £ Hydrus, 


3 





15 


56 78 


12 


7S. 




14 


203 * Phcenicis, 


2.3 





18 


1 43 


12 


12S. 




17 


204 * Andromedce, 


3 





30 


36 29 


56 







17 


205 * Cassiop., Scnedir, 

206 /S Ceti, Deneb Kaitos, 


3 





31 


5 55 


37 


13 




18 


3 





35 


12 18 


54 


17S. 




21 


207 y Cassiopeia, 


3 


o 


46 


41 59 


48 


41 




24 


208 * U. M. Alruccabah, 


2.3 


1 





19 88 


25 


7 




24 


209 /S Andro., Mirach, 


2 


1 





45 34 


44 


10 




2s 


210 J Cassio., Ruchbah, 


3 


1 


14 


57 59 


21 


54 


Dec. 


2 


211 * Eradani, Achernar, 


1 


1 


31 


21 58 


12 


37S. 




4 


212 t Cassiopeia, 


3 


1 


42 


11 62 


50 


42 




4 


213 I Ceti, Baton Kaitos, 


3 


1 


43 


35 11 


9 


36S. 




5 


214/3 Arietis, 


O 


1 


45 


45 20 


59 


30 




/ 


215 a Pisciurn,El Rischa, 


3 


1 


53 


3S 1 


57 


19 




7 


216 y Andro., Almaach, 


2 


1 


53 


54 41 


31 


32 




8 


217 * Arietis, or El Nath 


2 


1 


57 


47 22 


40 


11 




11 


218 o Ceti, Mira, 


3 


2 


10 


36 3 


43 


59S. 




15 


219/ Ceti, 


s 


2 


30 


38 ! 


23 


15S. 




15 


220 s Ceti, 


3 


2 


31 


31 Jl2 


34 


49S. 




16 


221 y Ceti, 


3 


2 


34 


38 ! 2 


31 


57 




20 


222 y Persei, 


3 


2 


52 


13 52 


50 


46 




20 


223 x Ceti, Menkar, 


2 


2 


53 


33 1 3 


25 


54 




21 


224^ Persei, Algol, 


var. 


2 


56 


52 |40 


18 


30 




23 


225;* Fornax Chemica, 


3 


3 


5 


20 


29 


39 


5CS. 




23 


226 p Eridani, 


3 


3 


7 


31 


9 


26 


31S. 




25 


227 U Persei, Algeneb, 


2 


3 


12 


26 


49 


15 


38 




27 


228* Eridani, 


3 


3 


25 


32 


10 


1 


26S. 




29 


229 / Persei, 


3 


3 


31 


4 


47 


14 


54 




30 


230V Eridani, 


3 


3 


35 


31 


10 


20 


16S. 




30 


231 a Pleiades, Alcyone, 


3 


3 


37 


34 


23 


35 


4 






23a 


if Persei, 


3 


3 


44 





31 


23 


26 


Jan. 


~\ 



TABLE Hi. 

Exhibiting the Sun's Right Ascension, in Time, for every day in th& 
year. 



I 


January. 


February. 


March. 


April. 


May. 


June. 


| 




h. m. s. 


h. m. s. 


h. m. s. 


h. m. s. 


h. m. s. 


h. in. s. 




I 


18 46 21 


20 58 43 22 47 51 


41 25 


2 32 36 


4 35 .4 


1 


2 


18 50 46 


21 2 47 22 51 35 


45 3 


2 36 25 


4 39 19 


2 


3 


18 55 11 


21 6 50 22 55 19 


48 42 


2 40 14 


4 43 25 


3 


4 


18 59 35 


21 10 53 22 59 3 


52 20 


2 44 4 


4 47 31 


4 


5 


19 3 59 


21 14 54 23 2 46 


55 59 


2 47 55 


4 51 38 


5 


6 


19 8 22 


21 18 5523 6 28 


59 57 


2 51 46 


4 55 45 


6 


7 


19 12 45 


21 22 55 23 10 10 


1 3 16 


2 55 37 


4 59 52 


7 


8 


19 17 7 


21 26 54 23 13 52 


1 6 56 


2 59 30 


5 3 59 


8 


9 


19 21 29 21 30 53 23 17 33 


1 10 35 


3 3 22 


5 8 7 


9 


10 


19 25 50 21 34 50 23 21 14 


1 14 15 


3 7 16 


5 12 15 


10 


11 


19 30 1121 38 47 23 24 54 


1 17 55 


3 11 10 


5 16 24 


11 


fa 


19 34 31,21 42 43 23 28 35 


1 21 35 


3 15 4 


5 20 32 


12 


1.3 


19 38 50,21 46 38 23 32 14 


1 25 15 


3 19 


5 24 41 


13 


14 


19 43 9 21 50 33 23 35 54 


1 28 56 


3 22 55 


5 28 50 


14 


J 5 


19 47 27 


21 54 27 23 39 34 


1 32 38 


3 26 52 


5 32 59 


15 


16 


19 51 45 


21 58 20 23 43 13 


1 36 19 


3 30 49 


5 37 9 


16 


17 


19 56 1 


22 2 12 23 46 52 


1 40 1 


3 34 46 


5 41 18 


17 


IS 


20 18 


22 6 4 23 50 31 


1 43 44 


3 38 44 


5 45 28 


18 


19 


20 4 33 22 9 55 23 54 9 


1 47 26 


3 42 43 


5 49 37 


19 


20 


20 8 48 22 13 45 23 57 48 


1 51 10 


3 46 42 


5 53 47 


20 


•21 


20 13 2 22 17 35 1 26 


1 54 53 


3 50 42 


5 57 57 


21 


22 


20 17 15 22 21 24 5 4 


1 58 37 


3 54 42 


6 2 7 


22 


23 


20 21 2722 25 13 8 43 


2 2 22 


3 58 44 


6 6 16 


23 


24 


20 25 39 22 29 1| 12 21 


2 6 7 


4 2 45 


6 10 26 


24 


25 


20 29 50|22 32 48 15 59 


2 9 53 


4 6 47 


6 14 35 


25 


26 


20 34 023 36 35' 19 37 


2 13 39 


4 10 49 


6 18 44 


26 


27 


20 38 929 40 21: 23 15 


2 17 25 


4 14 52 


6 22 54 


27 


28 


20 42 18 22 44 6 26 53 


2 21 12 


4 18 56 


6 27 3 


28 


29 


20 46 25 




30 31 


2 24 59 


4 23 


6 31 11 


29 


30 


20 50 32 




34 9 


2 28 47 


4 27 4 


6 35 20 


30 


31 


20 54 38 




37 47 




4 31 6 




31 



TAELE III.— Continued. 



J3 


July. 


August. 


Sept. 


Oct. 


Nov. 


Dec. 






h, m. g. 


h m. s. 


h. m. s. 


h. m. s. 


h. m. s. 


h. m. s. 




1 


6 39 28 


8 44 22 10 40 30 


12 28 35 14 24 45 16 28 29 


i 


2 


6 43 36 


8 48 15 10 44 8 


12 32 12 14 28 4l!l6 32 48 


2 


3 


6 47 44 


8 52 7! 10 47 45 


12 35 50 14 32 37 16 37 8 


3 


4 


6 51 52 8 55 59; 10 51 22 12 39 25 14 36 34 16 41 29 


4 


5 


6 55 59 


8 59 50; 10 54 59 12 43 6.14 40 32 16 45 50 


5 


6 


7 6 


9 3 40 10 58 36:12 46 45 14 44 30 16 50 12 


6 


7 


7 4 12 


9 7 30,11 2 12 12 50 24 14 43 30 16 54 34 


7 


8 


7 8 18 


9 11 19 11 5 48 12 54 4 14 52 30 16 58 57J 8 


9 


7 12 24 


9 15 S 11 9 24 12 57 41 14 56 31 17 3 20! 9 


10 


7 16 30 


9 13 56 11 13 13 1 24 15 34 17 7 44 10 


11 


7 20 35 


9 22 44 11 16 36 13 5 5 15 4 3717 12 9 11 


12 


7 24 39 


9 26 31|11 20 1243 8 47 15 8 41 17 16 33j 12 


13 


7 28 43 


9 30 1841 23 43 13 12 29 15 12 45 17 20 55 13 


14 


7 32 47 


9 34 4 11 27 23 13 16 12 15 16 51 17 25 24 14 


15' 


7 36 50| 9 37 49 11 30 59 13 19 55 15 20 57 17 29 49 15 


16 


7 40 53: 9 41 34 11 34 34 13 23 38 15 25 5 17 34 15 16 


17 


7 44 55: 9 45 19 11 38 10 13 27 23 15 29 13 17 38 41 17 


18 


7 48 57 9 49 3 11 41 45 13 31 8 15 33 22 17 43 8 


13 


19 


7 52 58i 9 52 46 11 45 21 13 34 53 15 37 32 17 47 34 


19 


20 


7 56 59 1 9 56 29,11 48 56 13 38 39 15 41 42 17 52 1 


20 


21 


8 59 10 12 11 52 32 13 42 26 15 45 54 17 56 27 


21 


22 


8 4 59 10 3 54 11 56 8 13 46 13 15 50 6 18 54 


22 


23 


8 8 58 10 7 35 11 59 43 13 50 1 15 54 19 18 5 21 


23 


24 


8 12 56 10 11 16 12 3 19 13 53 50 15 58 33 13 9 47 


24 


25 


8 16 54 10 14 57 12 6 55 13 57 39 16 2 47 13 14 14 


25 


26 


8 20 52 10 IS 37 12 10 31 14 1 29 16 7 2 18 18 40| 26 


27 


8 24 48 10 22 17 12 14 7 14 5 20 16 11 IS 18 23 7| 27 


28 


8 28 44 10 25 56 12 17 44 14 9 12 16 15 35 18 27 33| 28 


29 


8 32 3940 29 35 12 21 21.14 13 4.16 19 52 18 31 59 29 


30 


8 36 34|10 33 14; 12 24 57 14 16 57,16 24 10 13 36 24 1 30 


31 


8 40 28 


10 36 52 




14 20 51 




18 40 50 


31 









TABLE IV. 








Showing the Right Ascension of the Mid-Heaven at 9 o'clock in the 


evening, for every day in the year. 


g 


January. 


February. 


March. 


April. 


May. 


June. 


a 




h. m. s. 


h. in. s. 


h. in. s. 


h. m. s. 


h. m. s. 


h ni. 6. 1 


1 


5 58 43 


7 47 51 


9 41 25 


11 32 36 


13 35 14 


I 


2 


3 50 4G 


6 2 47 


7 51 35 


9 45 3 


11 36 25 


13 39 19 


o 


3 


3 55 11 


6 6 50 


7 55 19 


9 48 42 


11 40 14 


13 43 25 


3 


4 


3 59 35 


G 10 53 


7 59 3 


9 52 20 


11 44 4 


13 47 31 


4 


5 


4 3 59 


G 14 54 


8 2 4G 


9 55 59 


11 47 55 


13 51 38 


5 


6 


4 8 22 


G 18 55 


8 G 28 


9 59 57JH 51 4G 


13 55 45 


6 


7 


4 12 45 


6 22 55 


8 10 10 


10 3 16 11 55 37 


13 59 52 


7 


8 


4 17 7 


G 26 54 


8 13 52 


10 G 56 


11 59 30 


14 3 59 


8 


9 


4 21 29 


G 30 53 


8 17 33 


10 10 35 


12 3 22 


14 8 7 


9 


10 


4 25 50 


G 34 50 


8 21 14 


10 14 15 


12 7 16 


14 12 15 


10 


11 


4 30 11 


G 38 47 


8 24 54 


10 17 55 


12 11 10 


14 16 24 


11 


12 


4 34 31 


G 42 43 


8 28 35 


10 21 35 


12 15 4 


14 20 32 


12 


13 


4 38 50 


G 4G 38 


8 32 14 


10 25 15 


12 19 


14 24 41 


13 


14 


4 43 9 


G 50 33 


8 35 54 


10 28 56 


12 22 55 


14 28 50 


11 


15 


4 47 27 


G 54 27 


8 39 34 


10 32 38 


12 26 52 


14 3-2 59 


IS 


IG 


4 51 45 


G 58 20 


8 43 13 


10 36 19 


12 30 49 


14 37 9 


16 


17 


4 5G 1 


7 2 12 


8 46 52 


10 40 1 


12 34 46 


14 41 18 


17 


18 


5 18 


7 G 4 


8 50 31 


10 43 44 


12 38 44 


14 45 28 


18 


19 


5 4 33 


7 9 55 


8 54 9 


10 47 26 


12 42 43 


14 49 37 


19 


20 


5 8 48 


7 13 45 


8 57 48 


10 51 10 


12 46 42 


14 53 47 


20 


21 


5 13 2 


7 17 35 


9 1 2G 


10 54 53 


12 50 42 


14 57 57 


21 


22 


5 17 15 


7 21 24 


9 5 4 


10 58 37 


12 54 42 


15 2 7 


22 


23 


5 21 27 


7 25 13 


9 8 43 


11 2 22 


12 58 44 


15 G 16 


23 


24 


5 25 39 


7 29 1 


9 12 21 


11 6 7 


13 2 45 


15 10 26 


21 


25 


5 29 50 


7 32 48 


9 15 59 


11 9 53 13 6 47 


15 14 35 


25 


2G 


5 34 


7 36 35 


9 19 37 


11 13 39|13 10 49 


15 18 44 


26 


27 


5 38 9 


7 40 21 


9 23 15 


11 17 25113 14 52 


15 22 54 


27 


28 


5 42 18 


7 44 6 


9 2G 53 


11 21 12il3 18 56 


15 27 3 


28 


29 


5 46 25 




9 30 31 


11 24 59J13 23 


15 31 11 


29 


30 


5 50 32 




9 34 9 


11 28 47113 27 4 


15 35 20 


30 


31 


5 54 38 




9 37 47 


1 


13 31 8 




31 



TABLE IV.— Continued. 



£ T 


July. August. 


Sept 


oc, ; 


Nov. 


Dec. 


I 




h. m. s. 1 h. m. s. 


h. in. s. 


h. ra. s. ! 


h. m. s. 


h. m. s. 




1 


15 39 28 17 44 22 19 40 30 


21 28 35 


23 24 45 


1 28 29 


1 


o 


15 43 36 17 48 15119 44 8 


21 32 12 23 28 41 


1 32 48 


2 


3 


15 47 44 17 52 7119 47 45 


21 35 50 23 32 37 


1 37 8 


3 


4 


15 51 52 17 55 59:19 51 22 


21 39 28 23 36 34 


1 41 29 


4 


5 


15 55 59 17 59 50 19 54 59 


21 43 6 23 40 32 


1 45 50 


5 


6 


16 6 18 3 40 19 58 36 


21 46 45 23 44 30 


1 50 12 


6 


7 


16 4 12 18 7 30,20 2 12 21 50 24 23 48 30 


1 54 34 


7 


8 


16 8 18 18 11 19 20 5 48 L 21 54 4 23 52 30 


1 58 57 


8 


9 


16 12 24 18 15 8 20 9 24121 57 44 23 56 31 


2 3 20 


9 


10 


16 16 30 18 18 56' 20 13 22 1 24 


34 


2 7 44 


10 


11 


16 20 35 18 22 44 20 16 36 22 5 5, 


4 37 


2 12 9 


11 


12 


16 24 39 18 26 31 20 20 12 22 8 47| 


8 41 


2 16 33 


12 


13 


16 28 43 18 30 18 20 23 4822 12 29; 


12 45 


2 20 58 


13 


14 


16 32 47 18 34 4 20 27 23 22 16 12 


16 51 


2 25 24 


14 


15 


16 36 50 18 37 49 20 30 5922 19 55 


20 57 


2 29 49 


15 


16 


16 40 53 18 41 34 20 34 3422 23 38 


25 5 


2 34 15 


16 


17 


16 44 55 18 45 19 20 38 10 22 27 23 


29 13 


2 38 41 


17 


18 


16 48 57 18 49 3 20 41 45J22 31 8 


33 22 


2 43 8 


ra 


19 


16 52 53 18 52 46 20 45 21 22 34 53 


37 32 


2 47 34 


19 


•20 


16 56 59 19 56 29 20 48 56|22 33 39, 


41 42 


2 52 1 


20 


21 


17 59 19 12 20 52 32,22 42 '26 


45 54 


2 56 27 


21 


2-3 


17 4 59 19 3 54 20 56 822 46 13 


50 6 


3 54 


22 


23 


17 8 58 19 7 35 20 59 43 22 50 1 


54 19 


3 5 21 


23 


24 


17 12 56 19 11 16 21 3 1922 53 50! 


58 33 


3 9 47 


24 


25 


,17 16 54 19 14 57 21 6 5522 57 39 


1 2 47 


3 14 14 


25 


26 


117 20 52 19 18 37 21 10 31;23 1 29 


1 7 2 


3 18 40 


26 


27 


17 24 48 19 22 17 21 14 7,23 5 20! 


1 11 18 


3 23 7 


27 


28 


17 28 44 19 25 56 21 17 44/23 9 12 


1 15 35 


3 27 33 


28 


29 


;i7 32 39 19 29 35 21 21 2123 13 4 


1 19 52 


3 31 59 


29 


30 


17 36 34 19 33 14 21 24 57 23 16 571 


1 24 10 


3 36 24 


30 


31 


17 40 28.19 36 52 




23 20 51 




3 40 50 


31 



TABLE V. 

Exhibiting the Sun's Declination for every day in the year. 



1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 



March. 



April. 



I 11\ o / tt 
23 1 52 17 8 5' 
22 56 45 16 51 46 
22 51 10 16 34 18 
22 45 8 16 16 32 
22 38 39 15 58 29 
22 31 43 15 40 11 
22 24 20 15 21 36 
22 16 31:15 2 46 
22 8 16J14 43 40 
21 59 34|14 24 20 
21 50 27|14 4 45 
21 40 55 13 44 56 
21 30 57 13 24 54 
21 20 34 13 4 39 
1 9 47 12 44 11 
20 58 35 12 23 30 
20 47 0|12 2 38 



20 35 
20 22 37 
20 9 51 
19 56 43 
19 43 12 
19 29 19 
19 15 4 
19 28 
IS 45 31 
18 30 14 
18 14 3' 
17 58 40 
17 42 24 
17 25 50 



11 41 34 

1 20 19 

10 58 53 

10 37 17 

10 15 31 

9 53 36 

9 31 31 

9 9 19 

8 46 58 

8 24 59 

8 1 53 



o t tt 
7 39 11 
7 16 22 
6 53 27 
6 30 26 
6 7 20 
5 44 9 
5 20 53 
4 57 34 
4 34 10 
4 10 43 
3 47 13 
3 23 40 
3 5 
2 36 28 
2 12 49 
1 49 9 
1 25 2' 
1 1 45 
38 3 
S. 14 21 
N. 9 20 
33 

56 41 

1 20 18 

1 43 54 

2 7 28 
2 30 58 

2 54 26 

3 17 50 

3 41 10 

4 426 



o / tt 
4 27 37 

4 50 43 

5 13 44 
5 36 39 

5 59 28 

6 22 11 

6 44 48 

7 7 1 
7 29 40 



May. 



June. 



/ /Ho i It 
15 22 22 1 44 
15 18 20 22 9 49 
15 36 16 22 17 30 

15 53 50 22 24 48 

16 11 8 22 31 43 
16 28 10 22 38 14 

16 44 56 22 44 21 

17 1 25 22 50 4 
17 17 37 22 55 23 

" 23 19 
23 4 50 



51 54 17 33 32 
8 14 1|17 49 10 
8 36 0;18 4 30 

8 57 50|l8 19 31 

9 19 32118 34 14 
9 41 4118 48 39 

10 2 27j 19 2 45 
10 23 40 19 16 31 

10 44 44 19 29 58 

11 5 36; 19 43 6 
11 26 18 19 55 53 

11 46 48 20 8 20 

12 7 8j20 20 26 
12 27 15 ! 20 32 12 

12 47 10' 20 43 36 

13 6 52 20 54 40 
13 2G 21 21 5 21 

13 45 3721 15 41 

14 4 40 21 25 38 
14 23 28 21 35 14 
14 42 2,21 44 2' 

|21 53 17 



23 8 56 
23 12 39 
23 15 56 
23 18 50 
23 21 18 
23 23 22 
23 25 1 
23 26 15 
23 27 5 
23 27 30 
23 27 29 
23 27 4 
23 2fi 15 
23 25 
23 23 21 
23 21 17 
23 18 48 
23 15 55 
23 12 38 



9 
10 
11 
12 

13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 



TABLE V.— Continued 



1 


July. 


August. 


Sept 


Oct 


Not. 


Dec. 






o / II 


o / // 


o l n\ o I If 


oi ll\ o i n 




1 


23 8 5618 6 40 


8 23 33 3 5 22 14 22 1921 47 34 


1 


2 


23 4 49 17 51 30 


8 1 441 3 28 40 14 41 30 21 56 46 


2 


3 


23 19 17 36 2 


7 39 48! 3 51 56 15 27 22 5 34 


3 


4 


22 55 25 17 20 17 


7 17 44 1 4 15 9 15 19 9 22 13 55 


4 


5 


22 50 6 17 4 16 


6 55 32; 4 38 20 15 37 37 22 21 51 


5 


6 


22 44 24 16 47 58 


6 33 14 5 1 27 15 55 49 22 29 21 


6 


7 


22 38 18 16 31 23 


6 10 49 5 24 30 16 13 45 22 36 25 


7 


8 


22 31 49 16 14 32 


5 48 18 5 47 30 16 31 25 22 43 2 


8 


9 


22 24 56 15 57 26 


5 25 41 


6 10 25 16 48 48 22 49 12 


9 


10 


22 17 40 15 40 4 


5 2 59 


6 33 15 17 5 55 22 54 55 


10 


11 


22 10 1 15 22 27 


4 40 11 


6 56 17 22 43 23 11 


11 


12 


22 1 59 15 4 35 


4 17 18 


7 18 40 17 39 14 23 5 


12 


13 


21 53 34 14 46 29 


3 54 20 


7 41 14 17 55 27 23 9 21 


13 


14 


21 44 46 14 28 8 


3 31 19 


8 3 41:18 11 21 23 13 14 


14 


15 


21 35 37 14 9 33 


3 8 13 8 26 2 18 26 55 23 16 40 


15 


16 


21 26 5 13 50 45 


2 45 3! 8 48 16 18 42 10 23 19 38 


16 


17 


21 16 11 13 31 43 


2 21 51! 9 10 22 18 57 5 23 22 7 


17 


18 


21 5 55 13 12 28 


1 58 36 9 32 21 19 11 40 23 24 9 


18 


19 


20 55 18 12 53 1 


1 35 181 9 54 11 19 25 54 23 25 42 


19 


20 


20 44 20 12 33 22 


1 11 58 10 15 52 19 39 47 23 26 47 


20 


21 


20 33 1 12 13 30 


48 36 10 37 24 19 53 19 23 27 24 


21 


22 


20 21 20 11 53 27 


25 13 10 58 47 20 6 28 23 27 32 22 


23 


20 9 20 11 33 13 


N. 1 49 11 19 59 20 19 15 23 27 13 23 


24 


19 56 59 11 12 48 


S. 21 36 11 41 1 20 31 40 23 26 24 21 


25 


19 44 19 10 52 12 


45 112 1 53 20 43 42 23 25 8| 25 


26 


19 31 18 10 31 26 


1 8 27 12 22 33 20 55 21 23 23 23j 26 


27 


19 17 59 10 10 31 


1 31 52 12 43 2 21 6 36 23 21 10 27 


28 


19 4 20' 9 49 25 


1 55 16 13 3 19 21 17 27 23 18 29j 28 


29 


18 50 22j 9 28 10 


2 18 4013 23 23 21 27 54 23 15 20! 29 


30 


18 36 6 9 6 46 


2 42 2jl3 43 15 21 37 56 23 11 43| 30 


31 


18 21 m 8 45 14 




14 2 54 




23 7 38 


3! 



TABLE VI. 

Exhibiting the Sun's mean place in the Ecliptic, or its Longitude, 
together with the Right Ascension, for every day in the year. 





January. 


February. 


March- 


April. 


cz 


Long. 


R. A. 


Long. 


R. A. 


Long. I R. A. 


Long, j R. A 




o 


1 


o / 


o 1 


o / 


o f 1 o f 


o / | o / 


1 


280 


3 C : 


281 35 


312 13 


314 41 


340 27 341 58 


11 1610 21 


2 


281 


41 


282 41 


313 14 


315 42 


341 28 342 54 


12 15 11 16 


3 


282 


42 283 48 


314 14 


316 42 


342 28' 343 50 


13 14 12 10 


4 


283 


43284 54 


315 15 


317 43 


343 28 344 46 


14 13 13 5 


5 


284 


441286 


316 16 


318 43 


344 28 345 41 


15 12 14 


6 


2S5 


45287 5 


317 17 


319 44 


345 28 346 37 


16 11 14 54 


7 


286 46'2S8 11 


318 17 


320 46 


346 28 347 32 


17 10 15 49 


S 


287 


48.289 17 


319 18 


321 44 


347 28 348 28 


18 9-16 44 


9 


2SS 


49 290 22 


320 19 


322 43 


348 27|349 23 


19 8 17 39 


10 


289 50,'291 28 


321 19 


323 43 


349 27 350 18 


20 6 18 34 


11 


290 


51292 33 


322 20 


324 41 


350 27 351 13 


21 5 19 29 


12 


291 


52 


293 38 


323 21 


325 40 


351 27 352 9 


22 4 20 24 


13 


292 


53 


294 43 


324 21 


326 40 


352 27 353 4 


23 321 19 


14 


293 


54 


295 47 


325 22 


327 38 


353 26'353 59 


24 1 22 14 


15 


294 


55 


296 52 


326 22 


328 37 


354 26 354 53 


25 0023 9 


16 


295 


57 


297 56 


327 23 


329 35 


355 26; 355 48 


25 5924 5 


17 


296 


58 


299 


328 23 


330 33 


356 25 356 43 


26 57125 


IS 


297 


59(300 4 
0301 8 


329 24 


331 31 


357 25| 357 3S 


27 56 25 56 


19 


299 


330 24 


332 29 


358 24 358 32 


28 54 26 51 


20 


300 


1 


302 12 


331 25 


333 27 


359 24 


•359 27 


29 53 27 47 


21 


301 


2 


303 15 


332 25 


334 24 


000 24 


22 


30 51|28 43 


22 


302 


3 


304 19 


333 26 


335 21 


1 23 


1 16 


31 50 


29 39 


23 


303 


4 


305 22 


334 26 


336 18 


2 22 


2 10 


32 4S 


30 35 


24 


304 


5 


306 25 


335 26 


337 15 


3 22 


3 5 


33 47 


31 32 


25 


305 


6 


307 27 


336 27 


338 12 


4 21 


4 


34 45 


32 28 


26 


306 


7 


308 30 


337 27 


339 9 


5 21 


4 54 


35 43 


33 25 


27 


307 


8 


309 32 


338 27 


340 5 


6 20 


5 49 


36 42 


34 21 


2S 


308 


9 


310 34 


339 27 


341 2 


7 19 


6 42 


37 40 


35 18 


20 


309 


10 


311 36 






8 18 


7 38 


38 38 


36 15 


30 


310 


11 


312 38 






9 18 


8 32 


39 36 37 12 


31 


311 


12 


313 39 






10 17 


9 27l 







TABLE VI.— Continued. 





May. 


June. 


July. 


August 


a 
P 


Long. 


R. A. 


Long. 


R. A. 


Long. 


R. A. 


Long. 


R. A. 




o / 


o 1 


o f 


o 1 


o t 


o / 


o / 


o f 


1 


40 34 


38 9 


70 25 


68 48 


99 4 


99 52 


128 40 


131 5 


2 


41 32 


39 6 


71 23 


69 50 


100 1 


100 54 


129 37 


132 4 


3 


42 31 


40 3 


72 20 


70 51 


100 59 


101 56 


130 35 


133 2 


4 


43 29 


41 1 


73 18 


71 53 


101 56 


102 58 


131 32 


134 


5 


44 27 


41 59 


74 15 


72 54 


102 53|104 


132 29 


135 


6 


45 25 


42 56 


75 12 


73 56 


103 50 105 1 


133 27 


135 55 


7 


10 23 


43 54 


76 10 


74 58 


104 47 


106 3 


134 24 


136 53 


8 


47 21 


44 52 


77 7 


76 


105 44 


107 5 


135 22 


137 50 


9 


48 19 


45 6 


78 4 


77 2 


106 42 


108 6 


136 20 


138 47 


10 


49 16 


46 49 


79 2 


78 4 


107 39 


109 7 


137 17 


139 44 


11 


50 14 


47 47 


79 59 


79 6 


108 36 110 9 


138 15 


140 41 


12 


51 12 


48 46 


80 56 


80 8 


109 33 111 10 


139 12 


141 38 


13 


52 10 


49 45 


81 54 


81 10 


110 311112 11 


140 10 


142 34 


14 


53 8 


50 44 


82 51 


82 13 


111 28 


113 12 


141 8 


143 31 


15 


54 6 


51 42 


S3 48 


S3 15 


112 25 


114 13 


142 5 


144 2" 


16 


55 3 


52 42 


84 46 


84 17 


113 22 


115 13 


143 3 


145 24 


17 


56 1 


53 41 


85 43 


85 20 


114 20 


116 14 


144 1 


146 20 


IS 


56 59 


54 41 


86 40 


86 22 


115 17 


117 14 


144 59 


147 16 


19 


57 57 


55 41 


87 37 


87 24 


116 14 


118 15 


145 56 


148 12 


20 


58 54 


56 41 


88 35 


8S 27 


117 11 


119 15 


146 54 


149 7 


21 


59 52 


57 41 


89 32 


89 30 


118 9 


120 15 


147 52 


150 3 


22 


50 50 


58 41 


90 29 


90 32 


119 6 


121 15 


148 50 


150 58 


23 


51 47 


59 41 


91 26 


91 34 


120 3 


122 14 


149 48 


151 54 


24 


62 45 


60 41 


92 24 


92 36 


121 1 


123 14 


150 46 


152 49 


25 


53 43 


61 42 


93 21 


93 39 


121 58 


124 14 


151 44 


153 44 


26 


54 40 


62 42 


94 18 


94 41 


122 55 


125 13 


152 42 


154 59 


27 


B5 38 


63 43 


95 15 


95 43 


123 53 


126 12 


153 39 


155 34 


2S 


66 35 


64 44 


96 13 


96 46 


124 50 


127 11 


154 37 


155 ^9 


29 


67 33 


65 45 


97 10 


97 48 


125 48 


128 10 


155 35 


157 & 


30 


68 30 


66 46 


98 7 


98 50 


126 45 


129 9 


156 34 


159 18 


31 


69 28 


67 47 






127 42 


130 7 


157 32 


15? 13 



29* 



TABLE V I.— Continued. 





| 

September. 


October. 


November. 


December. 


£ 


Long. 


R. A. 


Long. 


R. A. 


Long. 


R. A. 


Long. 


R. A. 




o / 


o 1 


o / 


o / 


o / 


o / 


o / 


o r 


i 


15S 30 


160 8 


187 47 


187 9 


218 34 


216 11 


248 50 


247 7 


2 


159 28 


161 2 


1S8 46 


188 3 


219 3f 


217 10 


249 51 


248 12 


3 


160 26 


16155 


189 45 


188 57 


220 3c 


218 9 


250 52 


249 17 


4 


16124 


162 51 


190 44 


189 52 


221 3c 


219 8 


25153 


250 22 


5 


162 22 


163 45 


19143 


190 47 


222 35 


220 8 


252 54 


25128 


6 


163 20 


164 39 


192 43 


191 41 


223 35 


221 8 


253 55 


252 33 


7 


164 19 


165 33 


193 42 


192 36 


224 36 


222 7 


254 56 


253 39 


8 


165 17 


166 27 


194 41 


193 31 


225 36 


223 8 


255 57 


254 44 


Q 


166 15 


167 21 


195 40 


194 26 


226 36 


224 8 


256 5S 


255 50 


10 


167 14 


16S 15 


196 40 


195 21 


227 37 


225 8 


257 59 256 55 


11 


168 12 


169 9 


197 39 


196 16 


22S 37 


226 9 


258 


258 2 


12 


169 11 


170 3 


198 39 


197 12 


229 37 


227 10 


260 1 


259 8 


13 


170 9 


170 57 


199 38 


198 7 


230 38 


228 11 


261 2 


260 15 


14 


171 8 


171 51 


200 3S 


199 3 


231 38 


229 13 


262 3 


26121 


15 


172 6 


172 45 


201 37 


199 59 


232 39 


230 14 


263 4 


262 27 


16 


173 5 


173 39 


202 37 


200 55 


233 39 


231 16 


264 6 


263 34 


17 


174 3 


174 32 


203 36 


201 51 


234 40 


232 18 


265 7 


264 40 


IS 


175 2 


175 26 


204 36 


202 47 


235 41 


233 20 


266 8 265 47 


19 


176 1 


176 20 


205 36 


203 43 


236 41 


234 23 


267 9 266 54 


20 


176 59 


177 14 


206 35 


204 40 


237 42 


235 26 


268 10 268 


24 


177 58 


17S S 


207 35 


205 36 


238 43 


236 2S 


269 11 269 7 


22 


178 57 


179 2 


208 35 


206 33 


239 43 


237 31 


270 12 270 14 


23 


179 56 


179 56 


209 35 


207 30 


240 44 


238 35 


271 14,271 20 


24 


180 54 


ISO 50 


210 35 


208 27 


241 45 


239 38 


272 15 272 27 


25 


18153 


18144 


21135 


209 25 


242 45 


240 42 


273 16 273 34 


26 


182 52 


182 38 


212 34 


210 22 


243 46 


24146 


274 17 274 40 


27 


183 51 


183 32 


213 34 


211 20 


244 47 


242 50 


275 IS 275 47 


2S 


184 50 


184 26 


214 34 


212 18 


245 48 


243 54 


276 19.276 53 


29 


185 49 


185 20 


215 34 


213 16 246 49 


244 5S 


277 21278 


30 


186 48 


186 141216 34|214 14|247 50 


246 2 


273 22'279 6 


31 




1 


217 34! 


215 131 


1 




279 23 , 


2S0 13 



TABLE VII. 



Exhibiting the Right Ascension and Declination of the Planets, and the 
time of their passing the Meridian, for 1833. 







Venus. 


Mars. 


Jupiter. 


Saturn. 


■B 


R. as- 


Dec- 


Pass 


R. as- 


Dec- Pass 


R.as-[ Dec-; Pass 


R. as- 


Dec-i Pass 


_o 


>, 


cen- 


Una- 


Mer. 


cen- 


lina- 


Mer. 


cen- lina- j Mer. 


cen- 


lina- j Mer. 


« 


P 


sion. 


tion. 




sion. 


tion. 




sion. tion. 


sion. 


tion. 






h. m. 


O ' 


h. m. 


h. m. 


O ' 


h. m. 


h. m. 1 ° ' h. m. 


h. m. 


° ' h. m. 


f^ 


1 


21 30 


16 44 


242 


3 13 


20 8 


8 24 


23 35 4 6 4 46 


11 57 


2 48 17 6 


j5 


7 


21 58 


14 12 


2 44 


3 16 


20 22 


8 1 


23 38 3 43 1 4 24 


11 57 


2 49 16 40 


3 
C 


13 


22 25 


11 27 


2 45 


3 21 


20 41 


7 40 


23 42, 3 18 1 4 1 


11 57 


2 51 16 14 


19 


22 51 


8 32 


2 46 


3 27 


21 4 


7 21 


23 46i 2 52 


3 39 


11 56 


2 55 15 48 


^ 


25 


23 17 


5 31 


2 46 


3 35 


21 29 


7 3 


23 50 2 24 


3 18 


11 56 


3 15 22 


£ 


1 


23 46 


1 54 


2 47 


3 44 


22 2 


6 44 


23 55 1 1 49 


2 55 


11 55 


3 9 14 52 


jjj 


7 


11 


1 14 


2 47 


3 54 


22 29 


6 29 


23 59 1 19 


2 35 


11 54 


3 17114 27 


a 


13 


35 


4 20 


2 47 


4 4 


22 57 


6 16 


4 47 


2 16 


11 53 


3 26 14 3 


5 


19 


58 


7 23 


2 47 


4 15 


23 24 


6 4 


9 15 


1 58 


11 51 


3 36 13 38 


fa 


25 


1 22 


10 19 


2 48 


4 27 


23 50 


5 53 


14 18 


1 40 


11 50 


3 47,13 14 




1 


1 37 


12 11 


2 48 


4 35 


24 5 


5 46 


17| 40 


1 23 


11 49 


3 54 12 58 


4 


7 


1 59 


14 53 


2 48 


4 48 


24 27 


5 36 


23 1 14 


1 11 


11 47 


4 6 12 34 


i 

s 


13 


2 22 


17 22 


2 4S 


5 1 


24 45 


5 28 


28 1 48 


54 


11 45 


4 18112 10 


19 


2 43 


19 37 


2 48 


5 15 


24 59 


5 19 


33 2 23 


038 


11 44 


4 29 11 46 


25 


3 3 


21 36 


2 46 


52S 


25 9 


5 11 


38j 2 57 


21 


11 42 


4 40 


11 23 




1 


3 24 


23 33 


242 


5 45 


25 16 


5 2 


45 


3 37 


2 


11 40 


4 53 


10 56 


_i 


7 


3 40 


24 53 


2 36 


5 59 


25 16 


4 55 


50 


4 11 


23 43 


11 38 


5 2 


10 32 


"S 


13 


3 53 


25 51 


2 26 


6 14 


25 11 


4 47 


55 


4 44 


23 26 


11 37 


5 11 


10 9 


< 


19 


4 1 


26 26 


2 13 


6 29 


25 2 


4 40 


1 1 


5 17 


23 9 


11 36 


5 19 


9 46 




25 

1 


4 5 


26 33 


1 54 


6 44 


24 46 


4 33 


1 6 


5 50 


22 52 


11 34 


5 25 


9 22 




4 3 


26 8 


1 29 


6 59 


24 26 


4 25 


1 11 


6 22 


22 35 


11 34 


5 30 


S 58 




7 


3 54 


25 4 


58 


7 14 


24 


4 17 


1 16 


6 53 


22 17 


11 33 


5 34 


8 35 


>> 


13 


3 42 


23 22 


21 


7 29 


23 29 


4 8 


1 21 


7 23 


21 58 


11 32. 


5 36 


8 11 


s 


19 


3 27 


21 13 


23 37 


7 44 


22 52 


4 


1 26 


7 52 


21 40 


11 32 


5 37 


7 47 




25 


3 15 


IS 58 


23 2 


7 59 


22 11 


3 50 


1 31 


8 20 


21 20 


11 32 


5 36 


723 




I 


~3~6 


16 45 


22 25 


8 16 


21 16 


3 39 


1 37 


8 51 


20 57 


11 32 


5 34 


6 54 


c5 

G 


7 


3 4 


15 28 


21 59 


8 31 


20 23 


3 30 


1 41 


9 11 


20 37 


11 32 


5 30 


6 30 


13 


3 7 


14 SO 


21 39 


8 46 


19 26 


3 19 


1 46 


9 40 


20 17 


11 33 


5 24 


6 6 


£• 


19 


3 15 


14 44 


21 22 


9 


18 25 


3 9 


1 50 


10 2 


19 56 


11 34 


5 18 


542 




25 


327 


15 5 


21 10 


9 15 


17 19 


2 59 


1 54 


10 23 


19 35 


11 35 


5 10 


5 18 



TABLE VII. for 1833— Contlnueu. 





A 


Venus. 


Mars. 


Jupiter. 


Saturn. 


s 


R. as- 


Dec- Pass 


R as- 


Dec- Pass 


R. as- Dec- Pass 


R. as- 


Dec- 


Pass 


5 


;? 


cen- 


ina- 


Mer. 


cen- 


lina- 


Mer. 


ccq- Una- j Mer. 


cen- 


lina- 


Mer. 


A 


sion 


tion. 




sion. 


tion. 




■ion. 


tion. 


sion. 


tion. 








h. in. 


O ' 


h. in. 


h. m. 


O ' 


ti. m.\h. m. 


° ' h. m. 


h. m. 


o * 


h. m 




1 


3 42 


15 43 21 


9 29 


16 9 


2 48 


1 57 


10 42 19 14 


11 36 


5 1 


465 


!►. 


7 


3 59 


16 33 20 53 


9 43 


14 56 


2 38 


2 1 


10 69 18 53 


11 38 


4 60 


4 31 


a 


13 


4 19 


17 30 20 48 


9 58 


13 9 


2 28 


2 4 11 15 18 31 


11 39 


439 


4 9 




19 


4 40 


18 25 20 46 


10 12 


12 19 


2 18 


2 7111 28 18 10 


11 41 


4 26 


3 46 




25 


5 3 
632 


19 17 

20 6 


20 45 


10 26 


10 56 


2 8 


2 9 


11 40 17 48 


11 43 


4 13 


324 




20 46 


10 42 


9 15 


1 56 


2 11 


11 6117 23 


11 45 


3 56 


2 69 


s 


7 


658 


20 36 20 49 


10 56 


7 47 


1 47 


2 13 


11 57 17 2 


11 47 


3 41 


239 


3 


13 


624 


20 5120 53 


11 10 


6 17 


1 38 


2 14 


12 2 16 40 


11 50 


3 26 


2 19 


3 


19 


6 52 


20 49 20 58 


11 24 


4 45 


1 30 


2 15 


12 4 16 19 


11 52 


3 10 


1 68 


^ 


25 


720 


20 30^1 3 


11 38 


3 11 


1 22 


2 15 


12 4 15 57 


11 55 


263 


1 39 




1 


7 63 


19 43 21 12 


11 55 


1 21 


1 13 


2 15 


12 115 31 


11 58 


233 


1 16 


s 


7 


8 21 


18 42 21 19 


12 9 


15 


1 6 


2 14 


11 56 15 9 


12 


2 16 


57 


a 


13 


8 60 


17 22 21 26 


12 23 


1 51 


59 


2 13 


11 43 14 46 


12 3 


1 58 


038 


« 


19 


9 18 


15 45 21 33 


12 38 


326 


51 


2 11 


11 39 14 23 


12 6 


1 41 


19 


OD 


25 


9 46 


13 51 21 39 


12 52 


6 2 


44 


2 9 


11 27|13 69 


12 8 


1 23 


1 




1 


10 14 


11 42 21 45 


13 7 


6 37 


37 


2 7 


11 14,13 35 


12 11 


1 6 


23 33 


« 


7 


10 41 


9 20 21 61 


13 22 


8 10 


030 


2 4 


11 13 11 


12 14 


49 23 19 


| 


13 


11 9 


6 43 21 66 


13 37 


9 43 


023 


2 1 


10 44,12 46 


12 17 


31:23 


19 


11 36 


4 8;22 1 


13 52 


11 13 


16 


1 58110 27|12 20 


12 19 


15 22 40 





25 


12 3 


1 21(22 5 


14 8 


12 41 


9 


1 65 


10 11 11 64 


12 22 


122 20 




1 


12 35 


1 67 22 10 


14 26 


14 19 


1 


1 52 


9 52 11 24 


12 25 


19 ! 21 66 


1 


7 


13 2 


4 48 22 13 


14 43 


15 40 


23 52 


1 49 


9 3610 67 


12 27 


034 21 34 


13 


13 30 


7 36:22 17 


14 59 


16 57 


23 44 


1 46 


922 


10 30 


12 29 


47121 12 


o 


19 


13 58 


10 18 


& 20 


15 16 


18 9 


23 36 


1 43 


9 9 


10 3 


12 32 


1 20 60 


K 


25 


14 27 


12 53 


22 23 


15 33 


19 15 


23 28 


1 41 


8 59 


9 35 


12 34 


1 12 


20 26 




I 


14 66 


16 17 


22 27 15 61 


20 17 


23 20 


1 40 1 8 50 


9 8 


12 36 


1 23 


20 a 


e 


7 


16 26 


17 28 


22 3116 9 


21 11 


23 12 


1 38 


8 45 


8 41 


12 37 


1 32 


19 3=* 


s 


13 


16 67 


19 21 


22 35 16 27 


21 59 


23 4 


1 37 


8 42 


8 14 


12 3? 


1 40 


19 13 


1 


19 


16 28 


20 66 


22 40116 46 


22 40 


22 56 


1 37 


8 41 


7 47 


12 a 


1 47 


H 48 


^3 


!25 


17 


22 8 


22 45 


|17 5 


23 13 


22 48 


1 37 


8 44 


7 20 


12 41 


1 53 


16 & 



TABLE VII. for 1836. 







Venus. 


MiLRS. 


Jupiter. 


Satcrn. 


« i * 


R. as- 


Dec- Pass 


R.as 


Dec- Pass 


R.as-' Dec- 


Pass 


R.as- Dec-I Piss 


c ^ 


cen- 


lina- Mer. 


cen- 


lina- 


Mer. 


cen- lina- 


Mer. 


; cen-jlina- Mer 


■s (S 


sion. 


tion. 


sion. 


tion. 




sion. ition. 




sion. tioc. | 


f 


h. m. 


° ' h. m. 


h. m. 


O f 


h. m. 


h.m.!° ' 


h. m. 


h. m. 1° h. -n. 


& * 


20 18 


21 17 1 37 


18 31 


24 5 


2-3 49 


6 43 23 4 


12 5 


14 9|10 31 13 25 


& 5 


20 38 


20 8 1 42 


18 44 


23 55 


23 47 


6 45 23 7 


11 47 


14 10 10 35-19 11 


S ! 10 21 4 


18 29 1 48 


19 1 


23 36 


23 44 


6 42 23 11 


11 24 


14 llllO 41 118 52 


g ! 15 21 29 


16 37 1 53 


19 17 


23 11 


23 41 


6 40 23 14 11 2 


14 12110 45 IS 34 


-» 20 21 53 


14 33 1 58 


19 34 


22 39 


23 33 


6 37 23 17 10 40 


14 13J10 48 K 15 


9 122' 17 


12 20 2 2 


19 50 


22 1 


23 So 


6 35 23 20 10 17 
6 32 23 23j 9 47 


14 14 10 15 17 56 


.1 1 22 50 


9 2 7 


20 13 


20 57 


23 30 


14 15 10 53 17 29 


i* 1 5 23 8 


7 12 9 


20 26 


20 16 


23 27 


6 30 23 25 9 30 


14 15|10 53 17 li 


S i 10 23 30 


4 27 2 12 


20 43 


19 19 


23 23 


6 28 23 27: 9 8 


14 15 


10 53 15 5» 


£ 1 15 23 54 


1 51 2 14 


20 58 


13 17 


23 20 


6 27 23 23! 8 4S 


14 15 


10 52 16 35 


8 20 


15 


46 2 17 


21 14 


17 10 


23 16 


6 26 23 29 8 27 


14 15 


10 50 16 15 


E* 


25 


37 


3 23 2 19 


21 30 


15 53 


23 11 


6 26 23 30 8 7 


14 15 


10 47; 15 55 




1 


59 


5 59 2 21 


21 45 


14 42 


23 7 


6 26 23 3l| 7 47 


14 15 


10 44 15 35 




5 


1 16 


8 lj 2 23 


21 57 


13 39 


23 4 


6 26 23 311 7 32 


14 14 


10 4115 13 


■g 


10 


1 38 


10 30 2 26 


22 13 


12 17 


22 59 


6 26 23 3l! 7 12 


14 13 


10 36 14 53 


ad 


15 


2 1 


12 52 2 28 


22 23 


10 53 


22 54 


6 27 23 31 6 54 


14 13 


10 30 14 33 


£ 


20 


223 


15 8; 2 31 


22 42 


9 25 


22 49 


6 23 23 31- 6 35 


14 12 


10 24 14 17 




25 


2 46J17 14| 2 34 


22 57 


7 56 


22 44 


6 29,23 30; 6 17 


14 10 


10 18 13 56 




1 


3 18i 19 54; 2 39 


23 17 


5 43 


22 37 


6 32 23 49; 5 52 


14 9 10 813 27 


-j 


5 


3 37 21 151 2 42 


23 29 


4 34 


22 33 


6 34 23 23 5 38 


14 8! 10 213 10 


10 | 4 1,'22 44! 2 46 


33 43 


3 1 


22 27 


6 36 23 26 5 20 


14 6 9 54 12 49 


§• 1 15 4 


23 57 


1 27 


22 22 


6 39 23 24, 5 3 


14 5 9 46 12 23 


< 20 


4 49 25 


254 


12 


6 


22 16 


6 42 23 22 ! 4 47 


14 3 9 33 12 7 




25 


5 13J25 45 


2 59 


26 


1 39 


22 11 


6 45 23 19; 4 30 

1 


14 2 9 31 11 46 




5 41 26 19 


3 3 


43 


3 30 


22 4 


6 49 23 15; 4 10 


14 Oi 9 22 11 20 




5 


6 0-26 23 


3 6 


054 


4 43 


21 59 


6 5223 ll! 3 53 


13 59| 9 16 11 4 


►, 


10 


6 22126 27 


3 9 


1 8 


6 12 


21 54 


6 55 23 ?! 3 42 


13 53! 9 9 10 43 


S 


15 


6 44:26 10 


3 11 


1 22 


7 40 


21 48 


6 59 23 2 3 26 


13 56 9 2 10 22 


20 7 6,25 40 


3 13 


1 36 


9 5 


21 43 


7 3 22 57; 3 10 


13 55 8 56 10 1 




25 


7 25 24 58 


3 13 


1 50 


10 2S 


21 37 


7 7,22 51 2 54 


13 54 8 51; 9 40 




1 


7 51 23 41 


3 11 


2 10 


12 19 


21 29 


7 13 22 41 2 33 


13 53 3 45' 9 11 




5 


8 4:22 49 


3 8 


2 22 


13 20 


21 25 


7 17 22 35 1 2 21 


13 52 3 42 8 55 


c 


10 


8 19j21 39 


3 32 


2 36 


14 32 


21 20 


7 2122 271 2 5 


13 51 . S 39 8 34 


3 


15 


8 31120 25 


2 56j 2 50 


15 41 


21 14 


7 26,22 19, 1 50 


13 51 i 8 37 9 !t 


"* 


20 


3 41 19 9 


2 461 3 5 16 46 


21 9 


7 30,22 9; 1 35 


13 oil 8 36 7 54 




25 


8 45j 


17 54 


2 341 


3 19 


17 47J 


21 4! 


7 35|22 0, 


1 20 


13 50' 


8 36, T 34 



TABLE VII. for 183^-Continued. 



4 

c 


03 


VgNUS. 


MAB8. 


Jupiter. 


Satcrh. 


R.as 


Dec- 


Pass 


R.as- 


Dec 


Pass 


R.as 


Dec- Pass 


R. as- 


Dec 


Pasa 


a 


5" 


era 


lina- 


Mer 


cen 


Una- 


Mer 


cen 


li na- 


Mer 


cen- 


lina- 


Mer 


1 


(3 


sion 


tion. 




sion. 


lion. 




sion 


tion. 




sion. 


tion. 








h. m 


O ' 


h. ra 


h. m. 


O ' 


h. m 


h. m 


o * 


i m 


h. in. 


O t 


h. in. 




i 


853 


16 29 


2 14 


3 37 


18 54 


20 58| 7 4C 


21 47 1 2113 50 


836 


7 10 




5 


8 52 


15 39 


1 58 


3 48 


19 35 


20 53 


7 4-1 


21 38 50|13 50 


8 3t- 


6 55 


~ 


10 


8 48 


14 44 


1 34 


4 3 


20 22 


20 48 


7 4£ 


21 27 


3' 


13 50 


8 40 


635 


<-> 


15 


8 40 


14 2 


1 7 


4 18 


21 4 


20 43 


7 54 


21 K 


02(J 


13 50 


843 


6 16 




20 


8 29 


13 35 


36 


4 32 


21 41 


20 3S 


7 5S 


21 2 


5 


13 51 


8 47 


5 57 




'25 


8 17 


13 21 


24 


4 47 


22 13 


20 33 


8 3 


20 5C 


23 47 


13 51| 8 52 


5 33 




1 


7 59 


13 24 


23 12 


5 7 


22 50 


20 26 


8 9 


20 31 


23 26 


13 52 


9 


5 11 


j 


5 


7 51 


13 35 


22 49 


5 19 


23 6 


20 22 


8 13 


20 20 


23 14 


13 53 


9 5 


4 56 


9 


10 


7 44 


13 54 


22 24 


5 33 


23 22 


20 16 


8 IS 


20 6 


22 59 


13 54 


9 13 


4 38 


to 


15 


7 41 


14 16 


22 2 


5 47 


23 33 


20 11 


8 22 


19 52 


22 41 


13 51 


920 


4 19 


< 


20 


7 43 


14 38 


22 44 


6 1 


23 40 


20 5 


8 21 


19 37 22 28 


13 57 


9 29 


4 1 




25 


7 48 


14 58 


21 30 


6 15 


23 42 


19 59 


8 31 


19 22 


22 13 


13 58 


938 


3 43 


c 


1 


8 


15 14 


21 16 


6 35 


23 37 


19 51 


8 37 


19 2 


21 51 


14 


9 51 


3 17 


Z 


5 


8 10 


15 17 


21 10 


6 45 


23 31 


19 50 


8 40 


13 50 


21 39 


14 2 


10 


3 3 


5 


10 


8 23 


15 11 


21 4 


6 59 


23 19 


19 40 


8 44 


13 35 


21 23 


14 4 


10 10 


2 45 




15 


8 39 


14 54 


21 


7 12 


23 4 


19 33 


8 4S 


13 21 


21 7 


14 6 


10 21 


2 27 


E. 


20 


8 55 


14 26 


20 57 


7 25 


22 46 


19 26 


8 52 


18 7 


20 51 


14 7 


10 32 


2 10 


£ 


25 


9 13 


13 46 


20 56 


7 37 


22 25 


19 IS 


8 55 


17 52 


20 35 


14 9 


10 44 


1 52 




1 


9 36 


12 41 


20 55 


7 52 


21 55 


19 10 


9 


17 37 


20 16 


14 12 


10 53 


1 3i 


w; 


5 


9 52 


11 49 


20 55 


8 1 


21 34 


19 3 


9 2 


17 26 


20 3 


14 14 


ll 7 


I 17 


Si 


19 


10 12 


10 33 


20 55 


8 13 


21 6 


18 55 


9 5 


17 14 


19 46 


14 16 


ll 19 


59 


2 


15 


10 32 


9 6 20 56 


8 24 


20 36 


18 46 


9 8 


17 2 


19 29 


14 13 


11 31 


42 


o 


20 


10 52 


7 30 20 57 


8 35 


20 6 


18 37 


9 11 


16 51 


19 12 


14 20 


11 43 


25 




25 


11 13 


5 46)20 58 


8 45 


19 35 


18 28 


9 13 


16 41 


13 55 


14 23 


11 55 


7 




1 


11 43 


3 721 


8 59 


18 51 


18 14 


9 16 


16 29 


18 30 


14 26 


12 11 


23 39 


o 


5 


12 1 31121 1 


9 6 


18 26 


18 5 


9 IS 


16 23 


18 16 


14 28 


12 20 


23 26 


2 


10 


12 21 


33121 3 


9 15 


17 56 


17 54 


9 19 


16 17 


17 53 


14 30 


2 32123 8 




15 


12 43 


2 40 21 5 


9 23 


17 27 


17 43 


9 21 16 12 


17 40 


14 33 


12 43:22 51 


I 


20 


13 5 


4 48121 7 


9 31 


17 


17 31 


9 22 16 8 


17 21 


14 35 12 56J22 33 


Z, 


25 


13 27 


6 57 21 10 


9 37 


16 37 17 18 


923 


16 6 


17 2 


14 37|l3 4(22 16 




1 


13 54 


9 28 21 13 


9 45 


16 12 17 ll 9 23 


16 5 


16 39 


14 40 13 ic'2l 55 


■ 


5 


14 13111 7;2l 16 


9 49 


15 59 16 50J 9 23 


16 6 


16 23 


14 41 13 24|21 41 


s 


10 


14 36! 13 5 21 20 


9 54 


15 47 


16 35j 9 23 


16 8 16 3 


14 44 13 33 21 24 




15 


15 14 57121 24 


9 57 15 39 


16 18j 9 22 


6 12 15 13 


14 46 13 42 21 6 


gg 


20 


15 24|16 4121 29 10 0|l5 38 


16 11 9 22 


16 17 15 22 


14 481 13 50 20 4< 


Q 


25 


15 491 


18 13, 


21 341 


10 1| 


5 42 


15 433 


9 20j 


6 2-i ; 


15 2 


14 491 


3 58, 


20 3< 





TABLE VIII. 








TABLE IX. 




To cl.ange degrees, minutes, and 


To change hours, minutes, and 


seconds of the equator, or of 




seconds, of sidereal time, into 


right ascension, into hours, mi- 




legrees, minutes, and seconds, 


nutes, and seconds, of sidereal 


of the equator, or right 


ascen- 


time. 


sion. 






Deg. 


H. M. 


Deg-. 


H. M. 


1 


S s 


,. 


s 


Min. 


D. M. 


Mln. 


D. M. 


ML 


M. S. 


Mi. 


M. S. 


S3 








Sec- 


m. a. 


Sec 


M. 8. 


See. 


S. Th. 


Sec. 


S. Th. 


3 


K £ 


8 


a 


Th. 


S. Th. 


Th. 


S. Th. 


1 


4 


31 


2 4 


70 


4 40 


1 


15 


1 


15 


31 


7 45 


2 


8 


32 


2 8 


80 


5 20 


o 


30 


2 


30' 


32 


8 


3 


12 


33 


2 12 


90 


6 


3 


45 


3 


45 


33 


8 15 


4 


16 


34 


2 16 


100 


6 40 


4 


60 


4 


I 


34 


8 30 


5 


20 


35 


2 20 


110 


7 20 


5 


75 


5 


1 15 


35 


8 45 


€ 


24 


36 


2 24 


120 


8 


6 


90 


6 


1 30 


36 


9 


7 


28 


37 


2 28 


130 


8 40 


7 


105 


7 


1 45 


37 


9 15 


8 


32 


38 


2 32 


1-10 


9 20 


8 


120 


8 


2 


38 


9 30 


9 


36 


39 


2 36 


150 


10 





135 


9 


2 15 


39 


9 45 


10 


40 


40 


2 40 


1G0 


10 40 


10 


150 


10 


2 30 


40 


10 


11 


44 


41 


2 44 


170 


11 20 


11 


165 


11 


2 45 


41 


10 15 


12 


48 


42 


2 481180 


12 


12 


180 


12 


3 


42 


10 30 


13 


52 


43 


2 52 1 190 


12 40 


13 


195 


13 


3 15 


43 


10 45 


14 


56 


44 


2 56 200 13 20" 


14 


210 


14 


3 30 


44 


11 


15 


1 


45 


3 210 14 


15 


225 


15 


3 45 


45 


11 15 


16 


1 4 


46 


3 4 220; 14 40 


It] 


240 


16 


4 


46 


11 30 


17 


1 8 


47 


3 8 230' 15 20 


17 


255 


17 


4 15 


47 


11 45 


18 


1 12 


48 


3 12:24016 


IS 


270 


18 


4 30 


48 


12 


19 


1 16 


49 


3 16 25016 40 


19 


285 


19 


4 45 


49 


12 15 


20 


1 20 


50 


3 20j260|17 20 


20 


300 


20 


5 


50 


12 30 


21 


1 24 


51 


3 34 270 18 


21 


315 


21 


5 15 


51 


12 45 


22 


1 28 


52 


3 28 280 18 40 


2- 


330 


22 


5 30 


52 


13 


23 


1 32 


53 


3 32 


290 19 2023 


345 


23 


5 45 


53 


13 15 


24 


1 36 


54 


3 36 


300 20 0*24 


360 


24 


6 


54 


13 30 


25 


1 40 


55 


3 40 


310,20 40-25 


375 


25 


6 15 


55 


13 45 


26 


1 41 


56 


3 44 


320 : 21 20 f 26 


390 


26 


6 30 


56 


14 


27 


1 *5 


57 


3 4>- 


330 22 027 


405 


27 


6 45 


57 


14 15 


28 


1 52 


58 


3 52 


310 22 40 28 


420 


2^ 


7 


58 


14 30 


29 


1 56 


59 


3 56 350 23 20 29 


435 


29 


7 15 


59 


14 45 


» 


2 \ 


« 


i <J 


\£ 


24 


3C 


^50 


30 


7 30 


60 


15 f 









TABLE X. 








TABLE XL 


Showing how many miles make a degree of lon- 


Of the Chmates be- 


gitude, in every degree of latitude. 


tween the Equator 




and the Polar Un- 


Deg. 


Geo. 


Eng. Deg. 


Geo. 


Eng. 


Des. 


Geo. 


Eng. 


cles. 


ut 


Miles. 
59.99 


Miles. 


Lat. 


Miles. 


Miles 


Lat. 


Miles 


Miles 




1 


69.06 


31 


51.43 


59.13 


61 


29.09 


33.45 


iJfsltil 


li 


2 


59.96 


69.03 


32 


50.88 


58.51 


62 


28.17 


32.40 


3 


59.92 


68.97 


33 


50.32 


57.87 


63 


27.24 


31.33 


o T 


rff|ZS3 


* 


59.85 


68.90 


34 


49.74 


57.20 


64 


26.30 


30.24 


5" 


5" • "| 


5s5 = 


c 


59.77 


68.81 


35 


49.15 


56.51 


65 


25.36 


29.15 






J " 


6 


59.67 


68.62 


36 


48.54 


55.81 


66 


24.40 


28.06 




d. m. h. m. 


d m. 


7 


59.55 


68.48 


37 


47.92 


55.10 


67 


23.45 


26.96 


1 


634 12 30 


8 34 


8 


59.42 


6S.31 


33 


47.28 


54.37 


68 


22.48 


25.85 


2 


1644 13 00 


810 


9 


59.26 


68.15 


39 


46.63 


53.62 


69 


21.50 


24.73 


3 


2412 13 30 


728 


10 


59.09 


67.95 


40 


45.96 


5285 


70 


20.52 


23.60 


4 '3048 14 00 


6 36 


11 


53.S9 


67.73 


41 


45.28 


52.07 


71 


19.53 


22.47 


5 3631 14 30 


5 43 


12 


58.69 


67 43 


42 


44.59 


51.27 


72 


18.54 


21.32 


6 4124 15 00 


453 


13 


53.46 


67.2! 


43 


43 88 


50.46 


73 


17.54 


20.17 


7 14532 15 30 


4 8 


U 


53.22 


66.95 


44 


43.16 


49.63 


74 


16.54 


19.02 


8 149 2 16 00 


3 30 


15 


57.95 


66.65 


45 


42.43 


48.78 


75 


15.53 


17.86 


9 5159 16 30 


2 57 


16 


57.67 


66.31 


46 


41.68 


47.93 


76 


14.52 


16.70 


10 5430 17 00 


231 


17 


57.38 


65.98 


47 


40.92 


47.06 


77 


13.50 


15.52 


11 5638 17 30 


2 8 


IS 


57.06 


65.62 


43 


40.15 


46.16 


7S 


12.48 


14.35 


12 15827 18 00 


149 


19 


56.73 


65.24 


49 


39.36 


45.26 


79 


11.45 


13.17 


13 15959 18 30 


132 


20 


56.38 


64.84 


50 


38.57 


44.35 


SO 


10.42 


11.98 


14 16118 19 00 


1 \9 


21 


56.01 


64.42 


51 


37.76 


43.42 


81 


9.38 


10.79 


15 6226 19 30 


1 8 


22 


55.63 


63.97 


52 


36.94 


42.48 


82 


8.35 


9-59 


16 16322 20 00 


56 


23 


55.23 


63.51 


53 


36.11 


41.53 


S3 


7.31 


8-41 


17 


6410 20 30 


48 


24 


54.81 


63.03 


54 


35.27 


40.56 


S4 


6.27 


7.21 


18 


6450 21 00 


43 


2.5 


54.33 


62.53 


55 


34.41 


39.53 


S5 


5.22 


6-00 


19 


6522 21 30 


3-2 


26 


53.93 


62.02 


56 


33.53 


as 58 


56 


4.18 


4.81 


20 


6548 22 00 


26 


2? 


53.46 


61.48 


57 


32.63 


37.58 


S7 


3.14 


3.61 


21 


66 5 22 30 


17 


2S 


52.97 


60.93 


53 


31.79 


36.57 


83 


2.09 


241 


22 


6621 23 00 


16 


a 


52.43 


60.35 


59 


30.90 


35.54 


S9 


1.05 


1.21 


23 


6629' 23 30 


3 


29 


51.96 


59.75 


60 


30.00 


34.50 


90 


000 


0.00 


24 


6632(24 00 


2 



TABLE XII. 
Of the Climates between the Polar Circles and the Poles. 



p_j, ln | Where the Breadths ru _. . Where the 

lit l0 "S est ofthe mail Lai longe8t 
Lat day Is. Climates. mates - lM - day Is. 



d. m. 
30orl. 
60 2, 
90 a 



d. m. 
77 40 
82 50 
90 00 



120 or 4 
150 6 
180 6 



Breadth! 

of the 
Climates. 



4 35 

6 19 

7 1 



TABLE XIII. 

Showing the Latitude and Longitude of some of the principal places in 
the United States, &c, with their Distance from the city of Wash- 
ington. 

The Longitudes are reckoned from Greenwich. 

71u Capitals (seats of Government) of the States and Territories are 
designated by Italic letters. 



Albany (Capitol^ . 
Alexandria, .... 
Annapolis, .... 
Auburn, .... 

Augusta, 

Augusta (State House), 
Baltimore (Battle Monument), 
Bangor (Court House), . 
Barnstable (Old Court House), 
Batavia, .... 

Beaufort, 

Boston (State House), . 
Bristol (Hotel), .... 
Brooklyn (Navy Yard), 
Brunswick (College), 

Puffalo, 

Cambridge (Harvard Hall), 

Camden, .... 

Canandaigua, .... 

Cape Cod (Light-House), . 

Charleston (College), 

Charlestown <,Navy Yard), . 

Cincinnati, .... 

Coluvibia, .... 

Colutnbus t .... 

Concord (State House), 

Dedham (Court House), . 

Detroit, .... 

Donaldsonville, 

Dorchester (AsL Observatory), ] 

Dover, 

Dover, 

Kaston (Court House) 

Eastport, . 

Edenton, 

Exeter, 

Frankfort, . 

Fredericksburg, 

Frederickton, 

Frederickstown, 

Georgetown, . 

Gloucester, 

Greensfield, . 

HagerstowB, 

Halifax, 





Latitude 


Longitud 


e, West, 


Dist from 




North. 


in degrees. 


in time. 


Wash'n. 




O r rr 


o / /' 


h.m. s. 


miles. 


N. Y. 


42 39 3 


73 44 49 


4 54 59.3 


376 


D. C. 


38 49 


77 4 


5 8 16 


6 


Md. 


39 


76 43 


5 6 52 


37 


N. Y. 


42 55 


76 28 


5 5 52 


339 


Ga. 


33 28 


81 54 


5 27 36 


580 


Me. 


44 18 43 


69 50 


4 39 20 


595 


Md. 


39 17 13 


76 37 50 


5 6 31.3 


38 


Me. 


44 47 50 


68 47 


4 35 8 


661 


Mass. 


41 42 9 


70 16 


4 41 4 


466 


N. Y. 


42 59 


78 13 


5 12 52 


376 


S. C. 


32 25 


SO 41 


5 22 44 


629 


Mass. 


42 21 15 


71 4 9 


4 44 16.6 


432 


R. I. 


41 39 58 


71 19 


4 45 36 


409 


N. Y. 


40 41 50 


73 59 30 


4 55 53 


227 


Me. 


43 53 


C9 55 1 


4 39 40.1 


563 


N. Y. 


42 53 


78 55 


5 15 40 


376 


Mass. 


42 22 15 


71 7 25 


4 44 29.7 


431 


S. C. 


34 17 


80 30 


5 22 12 


467 


N. Y. 


42 54 


77 17 


5 9 8 


336 


Mass. 


42 2 16 


70 4 


4 40 16 


50? 


S. C. 


32 47 


80 52 


5 20 3.5 


514 


Mass. 


42 22 


71 3 33 


4 41 14.2 


433 


Ohio. 


39 6 


84 22 


5 37 23 


497 


S. C. 


33 57 


81 7 


5 24 28 


500 


Ohio. 


39 47 


S3 3 


5 32 12 


3% 


N. II. 


43 12 29 


71 29 


4 45 56 


474 


Mass. 


42 16 


71 11 


4 44 44 


422 


Mich. 


12 24 


82 5S 


5 31 52 


526 


La. 


30 3 


91 2 


6 4 8 


1273 


Mass. 


42 19 15 


71 4 15 


4 44 17 


432 


Del. 


39 10 


75 30 


5 2 


114 


N. II. 


13 13 


70 54 


4 43 36 


490 


Md. 


33 46 10 


76 8 


5 4 32 


60 


Me. 


14 54 


66 56 


4 27 44 


778 


N. C. 


36 


77 7 


5 28 28 


234 


N. II. 


12 58 


70 55 


4 43 40 


471 


Ky. 


38 14 


84 40 


5 33 40 


551 


Va. 


38 34 


77 3S 


5 10 32 


56 


N B. 


16 3 


66 45 


4 27 




Md. 


39 24 


77 18 


5 9 12 


43 


S. C. 


33 21 


79 17 


5 17 8 


432 


Mass. 


12 36 


70 40 


4 42 40 


462 


Mass. 


12 37 


72 36 


4 50 24 


396 


Md. 


39 37 


77 35 


5 10 20 


6S 


n. a 


14 39 20 


63 36 40 


4 14 27 1 


936 



30 



TABLE XIII.— Continued. 







latitude 


Longitude, West, 


Diet I rum 






North. 


in degrees. 


in time. 


Wash'n 




O ' // 


O ' /' 


h.m. s. 


miles. 


HAllowell, . 


. , . Me. 


44 17 


69 50 


4 39 30 


593 


Harrisburgh, 


. . Pa. 


40 16 


76 50 


5 7 20 


110 


Hartford, . 


. Conn. 


41 46 


72 50 


4 51 20 


335 


Hudson, 
Huntsville, 


. . N. Y. 


42 14 


73 46 


4 55 4 


315 


, Ala. 


34 36 


86 67 


5 47 48 


726 


Indianapolis, 


Ind. 


39 55 


86 5 


6 44 20 


573 


Jackson, . 


. M'pi. 


32 23 


90 8 


6 32 


1035 


Jefferson, 


. M'ri. 


33 36 


92 8 


6 8 32 


980 


Kennebunk, 


. Me. 


43 25 


70 32 


4 42 8 


618 


Kingston, 


V. C. 


44 8 


76 40 


5 6 40 


456 


Knoxville, 


. Tenn. 


35 59 


83 54 


5 35 36 


616 


Lancaster, 


Pa. 


40 2 36 


76 20 33 


5 5 22.2 


109 


Lexington, 


. . Ky. 


38 6 


84 18 


5 37 12 


6& 


Little Rock, 


Ark. 


34 40 


92 12 


6 8 43 


1068 


Lockport, . 


. N. Y. 


43 11 


78 46 


5 15 4 


i(Xi 


Louisville, 


. . Ky. 


38 3 


85 30 


5 42 


690 


Lowell (St. Ann's Ch 


arch), . Mass. 


42 38 45 


71 18 45 


4 45 15 


439 


Lynchburgh, 


. . Va. 


37 36 


79 22 


5 17 28 


198 


Lynn, 

Slarblehead, 


. Mass. 


42 28 


70 57 


4 43 48 


441 


Mass. 


42 30 


70 52 


4 43 28 


450 


Middletown, 


. Conn. 


41 34 


72 39 


4 50 36 


325 


Milledgeville, 


Ga. 


33 7 


83 20 


5 33 20 


642 


Mobile, . 


. Ala. 


30 40 


88 11 


5 52 44 


1033 


Montpelier, . 


Vt. 


44 17 


72 36 


4 50 24 


524 


Monomoy Point Ligl 
Montreal, 


it, . . Mass. 


41 32 58 


70 1 31 


4 40 6.1 


500 


. L. C. 


45 31 


73 35 


4 54 20 


601 


Nantucket (Town II 


ill), . . Mass. 


41 16 32 


70 7 42 


4 40 30.S 


500 


Nashville, . 


Term. 


36 9 30 


86 49 3 


5 47 16.2 


714 


Natchez (Castle), 


. . M'pi. 


31 31 


91 21 42 


6 5 3S.8 


1146 


Newark, 


N. J. 


40 45 


74 10 


4 56 40 


215 


New Bedford (Marin 


era' Ch.\ Mass. 


41 38 7 


70 56 


4 43 44 


429 


Ncwbern, 


. N. C. 


35 20 


77 5 


5 8 20 


337 


Newburgh, . 


N. Y. 


41 31 


74 1 


4 56 4 


282 


Newburyport (2d Pr 


cs. ChA Mass. 


42 43 29 


70 62 


4 43 2S 


466 


Newcastle, 


. Del. 


39 40 


75 33 


5 2 8 


103 


New Haven (College 


X . . Conn. 


41 17 58 


72 57 46 


4 51 51.1 


301 


New London, . 


. Conn. 


41 22 


72 9 


4 43 36 


3>1 


New Orleans (City), 


. La. 


29 57 45 


90 6 49 


6 27.3 


1203 


Newport, . 


. R. I. 


41 29 


71 21 14 


4 45 24.9 


403 


New York (City Hal 


), . . N. Y. 


10 42 40 


74 I 8 


4 56 4.5 


226 


Norfolk (Fanner's 11 


ankX . V a . 


36 50 B0 


76 13 47 


5 5 15.1 


217 


Northampton (Manbi 


ju House), Mass. 


42 IS 55 


72 40 


4 50 40 


376 


Norwich, . 


. Conn. 


41 33 


72 7 


4 48 28 


362 


Pensacola, 


Fa. 


30 23 


87 12 


5 48 48 


1050 


Petersburg^!, . 
Philadelphia (Indepe 


. Va. 


37 13 54 


77 20 


5 9 20 


144 


ndencen.X Pa, 


39 56 59 


75 10 59 


5 43.9 


136 


Pittsburgh, 


. Pa. 


40 32 


30 8 


5 20 32 


223 


Pittsfield, (1st Cong. 


Church), Mass. 


42 26 59 


73 17 30 


4 53 10 


380 


Pittsburgh, 
Plymouth /Court IIo 


. N. Y. 
use), . Mass. 


44 42 

41 67 12 


73 26 
70 42 30 


4 53 44 
4 42 50 


539 
439 


Portland (Town IIou 


seX • • Me. 


13 39 26 


70 20 30 


4 41 22 


542 


Portsmouth (Coin 


HouseX N. H. 


43 4 54 


70 45 


4 43 


491 


Pnpghkcepsie, 


. N. Y. 


41 41 


73 55 


4 55 40 


301 


Princeton, . 


N.J. 


10 22 


74 35 


4 58 SO 


177 



TABLE XIII. -Continued. 



Providence (Old Col.), . . It. L 

Quebec (Castle), . . L. C. 

Raleigh, N. C. 

Richmond (Capitol), . . Va. 

Rochester (R'r House), . . N. Y. 

.Sable (Cape), ... Fa. 

Sackett's Harbour, . N. Y. 

Saco, Me. 

St Augustine, . . . .Fa. 

St. Louis, .... M'ri. 

Salem (E. I. M. Hall), . . Mass. 

Savannah, .... Ga. 

Schenectady, . . . . N. Y. 

Springfield (Court House), . Mass. 

Tallahassee, .... Fa. 

Taunton (Court House), . Mass. 
Toronto (York), . . .17. C. 

Trenton, . . . . N. J. 

Troy, N. Y. 

Tuscaloosa, .... Ala. 

University of Virginia, . . Va. 

Utica (Dutch Church), . N. Y. 
Vandalia, . . . .11. 

Vevay, Ind. 

Vincennes, .... Ind. 

Washington, (Capitol), D. C. 

Washington, .... M'pi. 

Wheeling, Va. 

Wilmington, .... Del. 

Wilmington, . . . . N. C. 

Worcester (Ant. Hall), . . Mass. 

Vork, ..... Me. 

k'nrk, . ... Pa. 



latitude Longitude, West, Dist frorc 
North, in degrees, in time. Wash'n. 



41 49 25 

40 47 17 
35 47 

"" 32 17 
8 17 
24 50 
43 55 
43 31 

29 48 30 
38 36 

42 31 19 

32 2 
42 48 

42 5 5S 

30 23 

41 5-4 9 

43 33 
40 14 

42 44 

33 12 

33 2 3 

43 6 49 
38 50 

M6 
38 43 

38 52 54 

31 36 
40 7 

39 41 

34 11 

42 16 9 

43 10 
'S3 5S 



71 25 56 
70 56 31 

78 48 

77 26 28 
77 51 
81 15 
75 57 
70 26 
81 35 
89 36 

70 54 
81 3 

73 55 

72 30 
84 30 

71 50 

79 20 

74 39 

73 40 
87 42 
73 31 29 

75 13 
89 2 
84 59 
87 25 

77 1 48 
91 20 

80 42 

75 28 

78 10 

71 49 
70 40 

76 40 



h.m. 

4 45 43.7 

4 43 46.1 

5 15 12 

5 9 49.9 
5 11 24 
525 
5 3 43 

4 41 44 

5 26 20 
5 58 24 

4 43 36 

5 24 12 
4 55 40 

4 60 24 

5 38 24 
4 44 20 

17 BO 
4 58 36 

4 54 40 
560 48 

5 14 5. 
5 52 
5 56 8 

) 56 
5 49 40 
" 8 7.! 

5 20 
5 22 48 

1 52 

12 40 

4 47 16 

4 42 40 

5 6 4/) 



miles. 
394 
781 
286 
122 
361 

407 
528 
841 
858 
446 
662 
391 
357 
896 
415 
500 
166 



781 
556 



146 
261 
108 
416 
394 
500 
87 



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